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<title>The Top-Level Context</title>
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<h2><span class="refentrytitle"><a name="cogl-2.0-experimental-The-Top-Level-Context.top_of_page"></a>The Top-Level Context</span></h2>
<p>The Top-Level Context — The top level application context.</p>
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<a name="cogl-2.0-experimental-The-Top-Level-Context.synopsis"></a><h2>Synopsis</h2>
<pre class="synopsis"><span class="returnvalue">CoglContext</span> * <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-context-new" title="cogl_context_new ()">cogl_context_new</a> (<em class="parameter"><code><span class="type">CoglDisplay</span> *display</code></em>,
<em class="parameter"><code><span class="type">GError</span> **error</code></em>);
<span class="returnvalue">gboolean</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-is-context" title="cogl_is_context ()">cogl_is_context</a> (<em class="parameter"><code><span class="type">void</span> *object</code></em>);
<span class="returnvalue">CoglDisplay</span> * <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-context-get-display" title="cogl_context_get_display ()">cogl_context_get_display</a> (<em class="parameter"><code><span class="type">CoglContext</span> *context</code></em>);
enum <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#CoglFeatureID" title="enum CoglFeatureID">CoglFeatureID</a>;
<span class="returnvalue">gboolean</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-has-feature" title="cogl_has_feature ()">cogl_has_feature</a> (<em class="parameter"><code><span class="type">CoglContext</span> *context</code></em>,
<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#CoglFeatureID" title="enum CoglFeatureID"><span class="type">CoglFeatureID</span></a> feature</code></em>);
<span class="returnvalue">gboolean</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-has-features" title="cogl_has_features ()">cogl_has_features</a> (<em class="parameter"><code><span class="type">CoglContext</span> *context</code></em>,
<em class="parameter"><code>...</code></em>);
<span class="returnvalue">void</span> (<a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#CoglFeatureCallback" title="CoglFeatureCallback ()">*CoglFeatureCallback</a>) (<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#CoglFeatureID" title="enum CoglFeatureID"><span class="type">CoglFeatureID</span></a> feature</code></em>,
<em class="parameter"><code><span class="type">void</span> *user_data</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-foreach-feature" title="cogl_foreach_feature ()">cogl_foreach_feature</a> (<em class="parameter"><code><span class="type">CoglContext</span> *context</code></em>,
<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#CoglFeatureCallback" title="CoglFeatureCallback ()"><span class="type">CoglFeatureCallback</span></a> callback</code></em>,
<em class="parameter"><code><span class="type">void</span> *user_data</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-push-matrix" title="cogl_push_matrix ()">cogl_push_matrix</a> (<em class="parameter"><code><span class="type">void</span></code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-pop-matrix" title="cogl_pop_matrix ()">cogl_pop_matrix</a> (<em class="parameter"><code><span class="type">void</span></code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-scale" title="cogl_scale ()">cogl_scale</a> (<em class="parameter"><code><span class="type">float</span> x</code></em>,
<em class="parameter"><code><span class="type">float</span> y</code></em>,
<em class="parameter"><code><span class="type">float</span> z</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-translate" title="cogl_translate ()">cogl_translate</a> (<em class="parameter"><code><span class="type">float</span> x</code></em>,
<em class="parameter"><code><span class="type">float</span> y</code></em>,
<em class="parameter"><code><span class="type">float</span> z</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-rotate" title="cogl_rotate ()">cogl_rotate</a> (<em class="parameter"><code><span class="type">float</span> angle</code></em>,
<em class="parameter"><code><span class="type">float</span> x</code></em>,
<em class="parameter"><code><span class="type">float</span> y</code></em>,
<em class="parameter"><code><span class="type">float</span> z</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-transform" title="cogl_transform ()">cogl_transform</a> (<em class="parameter"><code>const <a class="link" href="cogl-2.0-experimental-Matrices.html#CoglMatrix" title="CoglMatrix"><span class="type">CoglMatrix</span></a> *matrix</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-frustum" title="cogl_frustum ()">cogl_frustum</a> (<em class="parameter"><code><span class="type">float</span> left</code></em>,
<em class="parameter"><code><span class="type">float</span> right</code></em>,
<em class="parameter"><code><span class="type">float</span> bottom</code></em>,
<em class="parameter"><code><span class="type">float</span> top</code></em>,
<em class="parameter"><code><span class="type">float</span> z_near</code></em>,
<em class="parameter"><code><span class="type">float</span> z_far</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-perspective" title="cogl_perspective ()">cogl_perspective</a> (<em class="parameter"><code><span class="type">float</span> fovy</code></em>,
<em class="parameter"><code><span class="type">float</span> aspect</code></em>,
<em class="parameter"><code><span class="type">float</span> z_near</code></em>,
<em class="parameter"><code><span class="type">float</span> z_far</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-ortho" title="cogl_ortho ()">cogl_ortho</a> (<em class="parameter"><code><span class="type">float</span> left</code></em>,
<em class="parameter"><code><span class="type">float</span> right</code></em>,
<em class="parameter"><code><span class="type">float</span> bottom</code></em>,
<em class="parameter"><code><span class="type">float</span> top</code></em>,
<em class="parameter"><code><span class="type">float</span> near</code></em>,
<em class="parameter"><code><span class="type">float</span> far</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-get-modelview-matrix" title="cogl_get_modelview_matrix ()">cogl_get_modelview_matrix</a> (<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-Matrices.html#CoglMatrix" title="CoglMatrix"><span class="type">CoglMatrix</span></a> *matrix</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-set-modelview-matrix" title="cogl_set_modelview_matrix ()">cogl_set_modelview_matrix</a> (<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-Matrices.html#CoglMatrix" title="CoglMatrix"><span class="type">CoglMatrix</span></a> *matrix</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-get-projection-matrix" title="cogl_get_projection_matrix ()">cogl_get_projection_matrix</a> (<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-Matrices.html#CoglMatrix" title="CoglMatrix"><span class="type">CoglMatrix</span></a> *matrix</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-set-projection-matrix" title="cogl_set_projection_matrix ()">cogl_set_projection_matrix</a> (<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-Matrices.html#CoglMatrix" title="CoglMatrix"><span class="type">CoglMatrix</span></a> *matrix</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-set-viewport" title="cogl_set_viewport ()">cogl_set_viewport</a> (<em class="parameter"><code><span class="type">int</span> x</code></em>,
<em class="parameter"><code><span class="type">int</span> y</code></em>,
<em class="parameter"><code><span class="type">int</span> width</code></em>,
<em class="parameter"><code><span class="type">int</span> height</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-get-viewport" title="cogl_get_viewport ()">cogl_get_viewport</a> (<em class="parameter"><code><span class="type">float</span> v[4]</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-set-source" title="cogl_set_source ()">cogl_set_source</a> (<em class="parameter"><code><span class="type">void</span> *material</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-set-source-color" title="cogl_set_source_color ()">cogl_set_source_color</a> (<em class="parameter"><code>const <a class="link" href="cogl-2.0-experimental-Color-Type.html#CoglColor" title="struct CoglColor"><span class="type">CoglColor</span></a> *color</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-set-source-color4ub" title="cogl_set_source_color4ub ()">cogl_set_source_color4ub</a> (<em class="parameter"><code><span class="type">guint8</span> red</code></em>,
<em class="parameter"><code><span class="type">guint8</span> green</code></em>,
<em class="parameter"><code><span class="type">guint8</span> blue</code></em>,
<em class="parameter"><code><span class="type">guint8</span> alpha</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-set-source-color4f" title="cogl_set_source_color4f ()">cogl_set_source_color4f</a> (<em class="parameter"><code><span class="type">float</span> red</code></em>,
<em class="parameter"><code><span class="type">float</span> green</code></em>,
<em class="parameter"><code><span class="type">float</span> blue</code></em>,
<em class="parameter"><code><span class="type">float</span> alpha</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-set-source-texture" title="cogl_set_source_texture ()">cogl_set_source_texture</a> (<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-The-Texture-Interface.html#CoglTexture" title="CoglTexture"><span class="type">CoglTexture</span></a> *texture</code></em>);
<span class="returnvalue">void</span> * <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-get-source" title="cogl_get_source ()">cogl_get_source</a> (<em class="parameter"><code><span class="type">void</span></code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-push-source" title="cogl_push_source ()">cogl_push_source</a> (<em class="parameter"><code><span class="type">void</span> *material</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-pop-source" title="cogl_pop_source ()">cogl_pop_source</a> (<em class="parameter"><code><span class="type">void</span></code></em>);
#define <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#COGL-TYPE-BUFFER-BIT:CAPS" title="COGL_TYPE_BUFFER_BIT">COGL_TYPE_BUFFER_BIT</a>
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-clear" title="cogl_clear ()">cogl_clear</a> (<em class="parameter"><code>const <a class="link" href="cogl-2.0-experimental-Color-Type.html#CoglColor" title="struct CoglColor"><span class="type">CoglColor</span></a> *color</code></em>,
<em class="parameter"><code><span class="type">unsigned long </span> buffers</code></em>);
enum <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#CoglReadPixelsFlags" title="enum CoglReadPixelsFlags">CoglReadPixelsFlags</a>;
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-read-pixels" title="cogl_read_pixels ()">cogl_read_pixels</a> (<em class="parameter"><code><span class="type">int</span> x</code></em>,
<em class="parameter"><code><span class="type">int</span> y</code></em>,
<em class="parameter"><code><span class="type">int</span> width</code></em>,
<em class="parameter"><code><span class="type">int</span> height</code></em>,
<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#CoglReadPixelsFlags" title="enum CoglReadPixelsFlags"><span class="type">CoglReadPixelsFlags</span></a> source</code></em>,
<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-Common-Types.html#CoglPixelFormat" title="enum CoglPixelFormat"><span class="type">CoglPixelFormat</span></a> format</code></em>,
<em class="parameter"><code><span class="type">guint8</span> *pixels</code></em>);
<span class="returnvalue">void</span> <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-flush" title="cogl_flush ()">cogl_flush</a> (<em class="parameter"><code><span class="type">void</span></code></em>);
</pre>
</div>
<div class="refsect1">
<a name="cogl-2.0-experimental-The-Top-Level-Context.description"></a><h2>Description</h2>
<p>
A <span class="type">CoglContext</span> is the top most sandbox of Cogl state for an
application or toolkit. Its main purpose is to act as a sandbox
for the memory management of state objects. Normally an application
will only create a single context since there is no way to share
resources between contexts.
</p>
<p>
For those familiar with OpenGL or perhaps Cairo it should be
understood that unlike these APIs a Cogl context isn't a rendering
context as such. In other words Cogl doesn't aim to provide a state
machine style model for configuring rendering parameters. Most
rendering state in Cogl is directly associated with user managed
objects called pipelines and geometry is drawn with a specific
pipeline object to a framebuffer object and those 3 things fully
define the state for drawing. This is an important part of Cogl's
design since it helps you write orthogonal rendering components
that can all access the same GPU without having to worry about
what state other components have left you with.
</p>
</div>
<div class="refsect1">
<a name="cogl-2.0-experimental-The-Top-Level-Context.details"></a><h2>Details</h2>
<div class="refsect2">
<a name="cogl-context-new"></a><h3>cogl_context_new ()</h3>
<pre class="programlisting"><span class="returnvalue">CoglContext</span> * cogl_context_new (<em class="parameter"><code><span class="type">CoglDisplay</span> *display</code></em>,
<em class="parameter"><code><span class="type">GError</span> **error</code></em>);</pre>
<p>
Creates a new <span class="type">CoglContext</span> which acts as an application sandbox
for any state objects that are allocated.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>display</code></em> :</span></p></td>
<td>A <span class="type">CoglDisplay</span> pointer</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>error</code></em> :</span></p></td>
<td>A GError return location.</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>A newly allocated <span class="type">CoglContext</span>. <span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span>
</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 1.8</p>
<p class="stability">Stability Level: Unstable</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-is-context"></a><h3>cogl_is_context ()</h3>
<pre class="programlisting"><span class="returnvalue">gboolean</span> cogl_is_context (<em class="parameter"><code><span class="type">void</span> *object</code></em>);</pre>
<p>
Gets whether the given object references an existing context object.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>object</code></em> :</span></p></td>
<td>An object or <code class="literal">NULL</code>
</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>
<code class="literal">TRUE</code> if the handle references a <span class="type">CoglContext</span>,
<code class="literal">FALSE</code> otherwise</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 1.10</p>
<p class="stability">Stability Level: Unstable</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-context-get-display"></a><h3>cogl_context_get_display ()</h3>
<pre class="programlisting"><span class="returnvalue">CoglDisplay</span> * cogl_context_get_display (<em class="parameter"><code><span class="type">CoglContext</span> *context</code></em>);</pre>
<p>
Retrieves the <span class="type">CoglDisplay</span> that is internally associated with the
given <em class="parameter"><code>context</code></em>. This will return the same <span class="type">CoglDisplay</span> that was
passed to <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-context-new" title="cogl_context_new ()"><code class="function">cogl_context_new()</code></a> or if <code class="literal">NULL</code> was passed to
<a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-context-new" title="cogl_context_new ()"><code class="function">cogl_context_new()</code></a> then this function returns a pointer to the
display that was automatically setup internally.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>context</code></em> :</span></p></td>
<td>A <span class="type">CoglContext</span> pointer</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>The <span class="type">CoglDisplay</span> associated with the
given <em class="parameter"><code>context</code></em>. <span class="annotation">[<acronym title="Don't free data after the code is done."><span class="acronym">transfer none</span></acronym>]</span>
</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 1.8</p>
<p class="stability">Stability Level: Unstable</p>
</div>
<hr>
<div class="refsect2">
<a name="CoglFeatureID"></a><h3>enum CoglFeatureID</h3>
<pre class="programlisting">typedef enum {
COGL_FEATURE_ID_TEXTURE_NPOT_BASIC = 1,
COGL_FEATURE_ID_TEXTURE_NPOT_MIPMAP,
COGL_FEATURE_ID_TEXTURE_NPOT_REPEAT,
COGL_FEATURE_ID_TEXTURE_NPOT,
COGL_FEATURE_ID_TEXTURE_RECTANGLE,
COGL_FEATURE_ID_TEXTURE_3D,
COGL_FEATURE_ID_GLSL,
COGL_FEATURE_ID_ARBFP,
COGL_FEATURE_ID_OFFSCREEN,
COGL_FEATURE_ID_OFFSCREEN_MULTISAMPLE,
COGL_FEATURE_ID_ONSCREEN_MULTIPLE,
COGL_FEATURE_ID_UNSIGNED_INT_INDICES,
COGL_FEATURE_ID_DEPTH_RANGE,
COGL_FEATURE_ID_POINT_SPRITE,
COGL_FEATURE_ID_MAP_BUFFER_FOR_READ,
COGL_FEATURE_ID_MAP_BUFFER_FOR_WRITE,
COGL_FEATURE_ID_MIRRORED_REPEAT,
COGL_FEATURE_ID_SWAP_BUFFERS_EVENT,
} CoglFeatureID;
</pre>
<p>
All the capabilities that can vary between different GPUs supported
by Cogl. Applications that depend on any of these features should explicitly
check for them using <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-has-feature" title="cogl_has_feature ()"><code class="function">cogl_has_feature()</code></a> or <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-has-features" title="cogl_has_features ()"><code class="function">cogl_has_features()</code></a>.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><a name="COGL-FEATURE-ID-TEXTURE-NPOT-BASIC:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_TEXTURE_NPOT_BASIC</code></span></p></td>
<td>The hardware supports non power
of two textures, but you also need to check the
<a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#COGL-FEATURE-ID-TEXTURE-NPOT-MIPMAP:CAPS"><code class="literal">COGL_FEATURE_ID_TEXTURE_NPOT_MIPMAP</code></a> and <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#COGL-FEATURE-ID-TEXTURE-NPOT-REPEAT:CAPS"><code class="literal">COGL_FEATURE_ID_TEXTURE_NPOT_REPEAT</code></a>
features to know if the hardware supports npot texture mipmaps
or repeat modes other than
<code class="literal">COGL_RENDERER_PIPELINE_WRAP_MODE_CLAMP_TO_EDGE</code> respectively.
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-TEXTURE-NPOT-MIPMAP:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_TEXTURE_NPOT_MIPMAP</code></span></p></td>
<td>Mipmapping is supported in
conjuntion with non power of two textures.
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-TEXTURE-NPOT-REPEAT:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_TEXTURE_NPOT_REPEAT</code></span></p></td>
<td>Repeat modes other than
<code class="literal">COGL_RENDERER_PIPELINE_WRAP_MODE_CLAMP_TO_EDGE</code> are supported by the
hardware.
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-TEXTURE-NPOT:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_TEXTURE_NPOT</code></span></p></td>
<td>Non power of two textures are supported
by the hardware. This is a equivalent to the
<a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#COGL-FEATURE-ID-TEXTURE-NPOT-BASIC:CAPS"><code class="literal">COGL_FEATURE_ID_TEXTURE_NPOT_BASIC</code></a>, <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#COGL-FEATURE-ID-TEXTURE-NPOT-MIPMAP:CAPS"><code class="literal">COGL_FEATURE_ID_TEXTURE_NPOT_MIPMAP</code></a>
and <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#COGL-FEATURE-ID-TEXTURE-NPOT-REPEAT:CAPS"><code class="literal">COGL_FEATURE_ID_TEXTURE_NPOT_REPEAT</code></a> features combined.
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-TEXTURE-RECTANGLE:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_TEXTURE_RECTANGLE</code></span></p></td>
<td>Support for rectangular
textures with non-normalized texture coordinates.
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-TEXTURE-3D:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_TEXTURE_3D</code></span></p></td>
<td>3D texture support
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-GLSL:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_GLSL</code></span></p></td>
<td>GLSL support
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-ARBFP:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_ARBFP</code></span></p></td>
<td>ARBFP support
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-OFFSCREEN:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_OFFSCREEN</code></span></p></td>
<td>Offscreen rendering support
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-OFFSCREEN-MULTISAMPLE:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_OFFSCREEN_MULTISAMPLE</code></span></p></td>
<td>Multisample support for
offscreen framebuffers
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-ONSCREEN-MULTIPLE:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_ONSCREEN_MULTIPLE</code></span></p></td>
<td>Multiple onscreen framebuffers
supported.
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-UNSIGNED-INT-INDICES:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_UNSIGNED_INT_INDICES</code></span></p></td>
<td>Set if
<code class="literal">COGL_RENDERER_INDICES_TYPE_UNSIGNED_INT</code> is supported in
<a class="link" href="cogl-2.0-experimental-Indices.html#cogl-indices-new" title="cogl_indices_new ()"><code class="function">cogl_indices_new()</code></a>.
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-DEPTH-RANGE:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_DEPTH_RANGE</code></span></p></td>
<td>cogl_pipeline_set_depth_range() support
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-POINT-SPRITE:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_POINT_SPRITE</code></span></p></td>
<td>Whether
<a class="link" href="cogl-2.0-experimental-Pipeline.html#cogl-pipeline-set-layer-point-sprite-coords-enabled" title="cogl_pipeline_set_layer_point_sprite_coords_enabled ()"><code class="function">cogl_pipeline_set_layer_point_sprite_coords_enabled()</code></a> is supported.
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-MAP-BUFFER-FOR-READ:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_MAP_BUFFER_FOR_READ</code></span></p></td>
<td>Whether <a class="link" href="cogl-2.0-experimental-CoglBuffer---The-Buffer-Interface.html#cogl-buffer-map" title="cogl_buffer_map ()"><code class="function">cogl_buffer_map()</code></a> is
supported with CoglBufferAccess including read support.
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-MAP-BUFFER-FOR-WRITE:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_MAP_BUFFER_FOR_WRITE</code></span></p></td>
<td>Whether <a class="link" href="cogl-2.0-experimental-CoglBuffer---The-Buffer-Interface.html#cogl-buffer-map" title="cogl_buffer_map ()"><code class="function">cogl_buffer_map()</code></a> is
supported with CoglBufferAccess including write support.
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-MIRRORED-REPEAT:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_MIRRORED_REPEAT</code></span></p></td>
<td>Whether
<code class="literal">COGL_PIPELINE_WRAP_MODE_MIRRORED_REPEAT</code> is supported.
</td>
</tr>
<tr>
<td><p><a name="COGL-FEATURE-ID-SWAP-BUFFERS-EVENT:CAPS"></a><span class="term"><code class="literal">COGL_FEATURE_ID_SWAP_BUFFERS_EVENT</code></span></p></td>
<td> Available if the window system supports reporting an event
for swap buffer completions.
</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 1.10</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-has-feature"></a><h3>cogl_has_feature ()</h3>
<pre class="programlisting"><span class="returnvalue">gboolean</span> cogl_has_feature (<em class="parameter"><code><span class="type">CoglContext</span> *context</code></em>,
<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#CoglFeatureID" title="enum CoglFeatureID"><span class="type">CoglFeatureID</span></a> feature</code></em>);</pre>
<p>
Checks if a given <em class="parameter"><code>feature</code></em> is currently available
</p>
<p>
Cogl does not aim to be a lowest common denominator API, it aims to
expose all the interesting features of GPUs to application which
means applications have some responsibility to explicitly check
that certain features are available before depending on them.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>context</code></em> :</span></p></td>
<td>A <span class="type">CoglContext</span> pointer</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>feature</code></em> :</span></p></td>
<td>A <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#CoglFeatureID" title="enum CoglFeatureID"><span class="type">CoglFeatureID</span></a>
</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>
<code class="literal">TRUE</code> if the <em class="parameter"><code>feature</code></em> is currently supported or <code class="literal">FALSE</code> if
not.</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 1.10</p>
<p class="stability">Stability Level: Unstable</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-has-features"></a><h3>cogl_has_features ()</h3>
<pre class="programlisting"><span class="returnvalue">gboolean</span> cogl_has_features (<em class="parameter"><code><span class="type">CoglContext</span> *context</code></em>,
<em class="parameter"><code>...</code></em>);</pre>
<p>
Checks if a list of features are all currently available.
</p>
<p>
This checks all of the listed features using <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-has-feature" title="cogl_has_feature ()"><code class="function">cogl_has_feature()</code></a> and
returns <code class="literal">TRUE</code> if all the features are available or <code class="literal">FALSE</code>
otherwise.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>context</code></em> :</span></p></td>
<td>A <span class="type">CoglContext</span> pointer</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>...</code></em> :</span></p></td>
<td>A 0 terminated list of CoglFeatureIDs</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>
<code class="literal">TRUE</code> if all the features are available, <code class="literal">FALSE</code>
otherwise.</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 1.10</p>
<p class="stability">Stability Level: Unstable</p>
</div>
<hr>
<div class="refsect2">
<a name="CoglFeatureCallback"></a><h3>CoglFeatureCallback ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> (*CoglFeatureCallback) (<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#CoglFeatureID" title="enum CoglFeatureID"><span class="type">CoglFeatureID</span></a> feature</code></em>,
<em class="parameter"><code><span class="type">void</span> *user_data</code></em>);</pre>
<p>
A callback used with <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-foreach-feature" title="cogl_foreach_feature ()"><code class="function">cogl_foreach_feature()</code></a> for enumerating all
context level features supported by Cogl.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>feature</code></em> :</span></p></td>
<td>A single feature currently supported by Cogl</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>user_data</code></em> :</span></p></td>
<td>A private pointer passed to <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-foreach-feature" title="cogl_foreach_feature ()"><code class="function">cogl_foreach_feature()</code></a>.</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 0.10</p>
<p class="stability">Stability Level: Unstable</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-foreach-feature"></a><h3>cogl_foreach_feature ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_foreach_feature (<em class="parameter"><code><span class="type">CoglContext</span> *context</code></em>,
<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#CoglFeatureCallback" title="CoglFeatureCallback ()"><span class="type">CoglFeatureCallback</span></a> callback</code></em>,
<em class="parameter"><code><span class="type">void</span> *user_data</code></em>);</pre>
<p>
Iterates through all the context level features currently supported
for a given <em class="parameter"><code>context</code></em> and for each feature <em class="parameter"><code>callback</code></em> is called.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>context</code></em> :</span></p></td>
<td>A <span class="type">CoglContext</span> pointer</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>callback</code></em> :</span></p></td>
<td>A <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#CoglFeatureCallback" title="CoglFeatureCallback ()"><span class="type">CoglFeatureCallback</span></a> called for each supported feature</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>user_data</code></em> :</span></p></td>
<td>Private data to pass to the callback</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 1.10</p>
<p class="stability">Stability Level: Unstable</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-push-matrix"></a><h3>cogl_push_matrix ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_push_matrix (<em class="parameter"><code><span class="type">void</span></code></em>);</pre>
<p>
Stores the current model-view matrix on the matrix stack. The matrix
can later be restored with <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-pop-matrix" title="cogl_pop_matrix ()"><code class="function">cogl_pop_matrix()</code></a>.
</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-pop-matrix"></a><h3>cogl_pop_matrix ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_pop_matrix (<em class="parameter"><code><span class="type">void</span></code></em>);</pre>
<p>
Restores the current model-view matrix from the matrix stack.
</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-scale"></a><h3>cogl_scale ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_scale (<em class="parameter"><code><span class="type">float</span> x</code></em>,
<em class="parameter"><code><span class="type">float</span> y</code></em>,
<em class="parameter"><code><span class="type">float</span> z</code></em>);</pre>
<p>
Multiplies the current model-view matrix by one that scales the x,
y and z axes by the given values.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>x</code></em> :</span></p></td>
<td>Amount to scale along the x-axis</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>y</code></em> :</span></p></td>
<td>Amount to scale along the y-axis</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>z</code></em> :</span></p></td>
<td>Amount to scale along the z-axis</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="cogl-translate"></a><h3>cogl_translate ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_translate (<em class="parameter"><code><span class="type">float</span> x</code></em>,
<em class="parameter"><code><span class="type">float</span> y</code></em>,
<em class="parameter"><code><span class="type">float</span> z</code></em>);</pre>
<p>
Multiplies the current model-view matrix by one that translates the
model along all three axes according to the given values.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>x</code></em> :</span></p></td>
<td>Distance to translate along the x-axis</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>y</code></em> :</span></p></td>
<td>Distance to translate along the y-axis</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>z</code></em> :</span></p></td>
<td>Distance to translate along the z-axis</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="cogl-rotate"></a><h3>cogl_rotate ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_rotate (<em class="parameter"><code><span class="type">float</span> angle</code></em>,
<em class="parameter"><code><span class="type">float</span> x</code></em>,
<em class="parameter"><code><span class="type">float</span> y</code></em>,
<em class="parameter"><code><span class="type">float</span> z</code></em>);</pre>
<p>
Multiplies the current model-view matrix by one that rotates the
model around the vertex specified by <em class="parameter"><code>x</code></em>, <em class="parameter"><code>y</code></em> and <em class="parameter"><code>z</code></em>. The rotation
follows the right-hand thumb rule so for example rotating by 10
degrees about the vertex (0, 0, 1) causes a small counter-clockwise
rotation.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>angle</code></em> :</span></p></td>
<td>Angle in degrees to rotate.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>x</code></em> :</span></p></td>
<td>X-component of vertex to rotate around.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>y</code></em> :</span></p></td>
<td>Y-component of vertex to rotate around.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>z</code></em> :</span></p></td>
<td>Z-component of vertex to rotate around.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="cogl-transform"></a><h3>cogl_transform ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_transform (<em class="parameter"><code>const <a class="link" href="cogl-2.0-experimental-Matrices.html#CoglMatrix" title="CoglMatrix"><span class="type">CoglMatrix</span></a> *matrix</code></em>);</pre>
<p>
Multiplies the current model-view matrix by the given matrix.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>matrix</code></em> :</span></p></td>
<td>the matrix to multiply with the current model-view</td>
</tr></tbody>
</table></div>
<p class="since">Since 1.4</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-frustum"></a><h3>cogl_frustum ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_frustum (<em class="parameter"><code><span class="type">float</span> left</code></em>,
<em class="parameter"><code><span class="type">float</span> right</code></em>,
<em class="parameter"><code><span class="type">float</span> bottom</code></em>,
<em class="parameter"><code><span class="type">float</span> top</code></em>,
<em class="parameter"><code><span class="type">float</span> z_near</code></em>,
<em class="parameter"><code><span class="type">float</span> z_far</code></em>);</pre>
<p>
Replaces the current projection matrix with a perspective matrix
for a given viewing frustum defined by 4 side clip planes that
all cross through the origin and 2 near and far clip planes.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>left</code></em> :</span></p></td>
<td>X position of the left clipping plane where it
intersects the near clipping plane</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>right</code></em> :</span></p></td>
<td>X position of the right clipping plane where it
intersects the near clipping plane</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>bottom</code></em> :</span></p></td>
<td>Y position of the bottom clipping plane where it
intersects the near clipping plane</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>top</code></em> :</span></p></td>
<td>Y position of the top clipping plane where it intersects
the near clipping plane</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>z_near</code></em> :</span></p></td>
<td>The distance to the near clipping plane (Must be positive)</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>z_far</code></em> :</span></p></td>
<td>The distance to the far clipping plane (Must be positive)</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 0.8.2</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-perspective"></a><h3>cogl_perspective ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_perspective (<em class="parameter"><code><span class="type">float</span> fovy</code></em>,
<em class="parameter"><code><span class="type">float</span> aspect</code></em>,
<em class="parameter"><code><span class="type">float</span> z_near</code></em>,
<em class="parameter"><code><span class="type">float</span> z_far</code></em>);</pre>
<p>
Replaces the current projection matrix with a perspective matrix
based on the provided values.
</p>
<p>
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>You should be careful not to have to great a <em class="parameter"><code>z_far</code></em> / <em class="parameter"><code>z_near</code></em>
ratio since that will reduce the effectiveness of depth testing
since there wont be enough precision to identify the depth of
objects near to each other.</div>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>fovy</code></em> :</span></p></td>
<td>Vertical field of view angle in degrees.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>aspect</code></em> :</span></p></td>
<td>The (width over height) aspect ratio for display</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>z_near</code></em> :</span></p></td>
<td>The distance to the near clipping plane (Must be positive)</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>z_far</code></em> :</span></p></td>
<td>The distance to the far clipping plane (Must be positive)</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="cogl-ortho"></a><h3>cogl_ortho ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_ortho (<em class="parameter"><code><span class="type">float</span> left</code></em>,
<em class="parameter"><code><span class="type">float</span> right</code></em>,
<em class="parameter"><code><span class="type">float</span> bottom</code></em>,
<em class="parameter"><code><span class="type">float</span> top</code></em>,
<em class="parameter"><code><span class="type">float</span> near</code></em>,
<em class="parameter"><code><span class="type">float</span> far</code></em>);</pre>
<p>
Replaces the current projection matrix with an orthographic projection
matrix. See <a class="xref" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-ortho-matrix" title="Figure 1. ">Figure 1, “”</a> to see how the matrix is
calculated.
</p>
<p>
</p>
<div class="figure">
<a name="cogl-ortho-matrix"></a><p class="title"><b>Figure 1. </b></p>
<div class="figure-contents"><div><img src="cogl_ortho.png"></div></div>
</div>
<p><br class="figure-break">
</p>
<p>
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>This function copies the arguments from OpenGL's <code class="function">glOrtho()</code> even
though they are unnecessarily confusing due to the z near and z far
arguments actually being a "distance" from the origin, where
negative values are behind the viewer, instead of coordinates for
the z clipping planes which would have been consistent with the
left, right bottom and top arguments.</div>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>left</code></em> :</span></p></td>
<td>The coordinate for the left clipping plane</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>right</code></em> :</span></p></td>
<td>The coordinate for the right clipping plane</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>bottom</code></em> :</span></p></td>
<td>The coordinate for the bottom clipping plane</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>top</code></em> :</span></p></td>
<td>The coordinate for the top clipping plane</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>near</code></em> :</span></p></td>
<td>The <span class="emphasis"><em>distance</em></span> to the near clipping
plane (negative if the plane is behind the viewer)</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>far</code></em> :</span></p></td>
<td>The <span class="emphasis"><em>distance</em></span> for the far clipping
plane (negative if the plane is behind the viewer)</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 1.0</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-get-modelview-matrix"></a><h3>cogl_get_modelview_matrix ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_get_modelview_matrix (<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-Matrices.html#CoglMatrix" title="CoglMatrix"><span class="type">CoglMatrix</span></a> *matrix</code></em>);</pre>
<p>
Stores the current model-view matrix in <em class="parameter"><code>matrix</code></em>.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>matrix</code></em> :</span></p></td>
<td>return location for the model-view matrix. <span class="annotation">[<acronym title="Parameter for returning results. Default is transfer full."><span class="acronym">out</span></acronym>]</span>
</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="cogl-set-modelview-matrix"></a><h3>cogl_set_modelview_matrix ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_set_modelview_matrix (<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-Matrices.html#CoglMatrix" title="CoglMatrix"><span class="type">CoglMatrix</span></a> *matrix</code></em>);</pre>
<p>
Loads <em class="parameter"><code>matrix</code></em> as the new model-view matrix.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>matrix</code></em> :</span></p></td>
<td>the new model-view matrix</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="cogl-get-projection-matrix"></a><h3>cogl_get_projection_matrix ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_get_projection_matrix (<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-Matrices.html#CoglMatrix" title="CoglMatrix"><span class="type">CoglMatrix</span></a> *matrix</code></em>);</pre>
<p>
Stores the current projection matrix in <em class="parameter"><code>matrix</code></em>.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>matrix</code></em> :</span></p></td>
<td>return location for the projection matrix. <span class="annotation">[<acronym title="Parameter for returning results. Default is transfer full."><span class="acronym">out</span></acronym>]</span>
</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="cogl-set-projection-matrix"></a><h3>cogl_set_projection_matrix ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_set_projection_matrix (<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-Matrices.html#CoglMatrix" title="CoglMatrix"><span class="type">CoglMatrix</span></a> *matrix</code></em>);</pre>
<p>
Loads matrix as the new projection matrix.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>matrix</code></em> :</span></p></td>
<td>the new projection matrix</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="cogl-set-viewport"></a><h3>cogl_set_viewport ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_set_viewport (<em class="parameter"><code><span class="type">int</span> x</code></em>,
<em class="parameter"><code><span class="type">int</span> y</code></em>,
<em class="parameter"><code><span class="type">int</span> width</code></em>,
<em class="parameter"><code><span class="type">int</span> height</code></em>);</pre>
<p>
Replaces the current viewport with the given values.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>x</code></em> :</span></p></td>
<td>X offset of the viewport</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>y</code></em> :</span></p></td>
<td>Y offset of the viewport</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>width</code></em> :</span></p></td>
<td>Width of the viewport</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>height</code></em> :</span></p></td>
<td>Height of the viewport</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 1.2</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-get-viewport"></a><h3>cogl_get_viewport ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_get_viewport (<em class="parameter"><code><span class="type">float</span> v[4]</code></em>);</pre>
<p>
Stores the current viewport in <em class="parameter"><code>v</code></em>. <em class="parameter"><code>v</code></em>[0] and <em class="parameter"><code>v</code></em>[1] get the x and y
position of the viewport and <em class="parameter"><code>v</code></em>[2] and <em class="parameter"><code>v</code></em>[3] get the width and
height.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>v</code></em> :</span></p></td>
<td>pointer to a 4 element array
of <span class="type">float</span>s to receive the viewport dimensions. <span class="annotation">[<acronym title="Parameter for returning results. Default is transfer full."><span class="acronym">out</span></acronym>][<acronym title="Parameter points to an array of items."><span class="acronym">array</span></acronym> fixed-size=4]</span>
</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="cogl-set-source"></a><h3>cogl_set_source ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_set_source (<em class="parameter"><code><span class="type">void</span> *material</code></em>);</pre>
<p>
This function changes the material at the top of the source stack.
The material at the top of this stack defines the GPU state used to
process subsequent primitives, such as rectangles drawn with
<a class="link" href="cogl-2.0-experimental-Rectangles.html#cogl-rectangle" title="cogl_rectangle ()"><code class="function">cogl_rectangle()</code></a> or vertices drawn using <code class="function">cogl_vertex_buffer_draw()</code>.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>material</code></em> :</span></p></td>
<td>A <span class="type">CoglMaterial</span>
</td>
</tr></tbody>
</table></div>
<p class="since">Since 1.0</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-set-source-color"></a><h3>cogl_set_source_color ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_set_source_color (<em class="parameter"><code>const <a class="link" href="cogl-2.0-experimental-Color-Type.html#CoglColor" title="struct CoglColor"><span class="type">CoglColor</span></a> *color</code></em>);</pre>
<p>
This is a convenience function for creating a solid fill source material
from the given color. This color will be used for any subsequent drawing
operation.
</p>
<p>
The color will be premultiplied by Cogl, so the color should be
non-premultiplied. For example: use (1.0, 0.0, 0.0, 0.5) for
semi-transparent red.
</p>
<p>
See also <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-set-source-color4ub" title="cogl_set_source_color4ub ()"><code class="function">cogl_set_source_color4ub()</code></a> and <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-set-source-color4f" title="cogl_set_source_color4f ()"><code class="function">cogl_set_source_color4f()</code></a>
if you already have the color components.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>color</code></em> :</span></p></td>
<td>a <a class="link" href="cogl-2.0-experimental-Color-Type.html#CoglColor" title="struct CoglColor"><span class="type">CoglColor</span></a>
</td>
</tr></tbody>
</table></div>
<p class="since">Since 1.0</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-set-source-color4ub"></a><h3>cogl_set_source_color4ub ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_set_source_color4ub (<em class="parameter"><code><span class="type">guint8</span> red</code></em>,
<em class="parameter"><code><span class="type">guint8</span> green</code></em>,
<em class="parameter"><code><span class="type">guint8</span> blue</code></em>,
<em class="parameter"><code><span class="type">guint8</span> alpha</code></em>);</pre>
<p>
This is a convenience function for creating a solid fill source material
from the given color using unsigned bytes for each component. This
color will be used for any subsequent drawing operation.
</p>
<p>
The value for each component is an unsigned byte in the range
between 0 and 255.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>red</code></em> :</span></p></td>
<td>value of the red channel, between 0 and 255</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>green</code></em> :</span></p></td>
<td>value of the green channel, between 0 and 255</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>blue</code></em> :</span></p></td>
<td>value of the blue channel, between 0 and 255</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>alpha</code></em> :</span></p></td>
<td>value of the alpha channel, between 0 and 255</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 1.0</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-set-source-color4f"></a><h3>cogl_set_source_color4f ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_set_source_color4f (<em class="parameter"><code><span class="type">float</span> red</code></em>,
<em class="parameter"><code><span class="type">float</span> green</code></em>,
<em class="parameter"><code><span class="type">float</span> blue</code></em>,
<em class="parameter"><code><span class="type">float</span> alpha</code></em>);</pre>
<p>
This is a convenience function for creating a solid fill source material
from the given color using normalized values for each component. This color
will be used for any subsequent drawing operation.
</p>
<p>
The value for each component is a fixed point number in the range
between 0 and <code class="literal">1</code>.0. If the values passed in are outside that
range, they will be clamped.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>red</code></em> :</span></p></td>
<td>value of the red channel, between 0 and <code class="literal">1</code>.0</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>green</code></em> :</span></p></td>
<td>value of the green channel, between 0 and <code class="literal">1</code>.0</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>blue</code></em> :</span></p></td>
<td>value of the blue channel, between 0 and <code class="literal">1</code>.0</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>alpha</code></em> :</span></p></td>
<td>value of the alpha channel, between 0 and <code class="literal">1</code>.0</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 1.0</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-set-source-texture"></a><h3>cogl_set_source_texture ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_set_source_texture (<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-The-Texture-Interface.html#CoglTexture" title="CoglTexture"><span class="type">CoglTexture</span></a> *texture</code></em>);</pre>
<p>
This is a convenience function for creating a material with the first
layer set to <em class="parameter"><code>texture</code></em> and setting that material as the source with
cogl_set_source.
</p>
<p>
Note: There is no interaction between calls to cogl_set_source_color
and cogl_set_source_texture. If you need to blend a texture with a color then
you can create a simple material like this:
</p>
<pre class="programlisting">
material = cogl_material_new ();
cogl_material_set_color4ub (material, 0xff, 0x00, 0x00, 0x80);
cogl_material_set_layer (material, 0, tex_handle);
cogl_set_source (material);
</pre>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>texture</code></em> :</span></p></td>
<td>The <a class="link" href="cogl-2.0-experimental-The-Texture-Interface.html#CoglTexture" title="CoglTexture"><span class="type">CoglTexture</span></a> you want as your source</td>
</tr></tbody>
</table></div>
<p class="since">Since 1.0</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-get-source"></a><h3>cogl_get_source ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> * cogl_get_source (<em class="parameter"><code><span class="type">void</span></code></em>);</pre>
<p>
Returns the current source material as previously set using
<a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-set-source" title="cogl_set_source ()"><code class="function">cogl_set_source()</code></a>.
</p>
<p>
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>You should typically consider the returned material immutable
and not try to change any of its properties unless you own a
reference to that material. At times you may be able to get a
reference to an internally managed materials and the result of
modifying such materials is undefined.</div>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>The current source material.</td>
</tr></tbody>
</table></div>
<p class="since">Since 1.6</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-push-source"></a><h3>cogl_push_source ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_push_source (<em class="parameter"><code><span class="type">void</span> *material</code></em>);</pre>
<p>
Pushes the given <em class="parameter"><code>material</code></em> to the top of the source stack. The
material at the top of this stack defines the GPU state used to
process later primitives as defined by <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-set-source" title="cogl_set_source ()"><code class="function">cogl_set_source()</code></a>.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>material</code></em> :</span></p></td>
<td>A <span class="type">CoglMaterial</span>
</td>
</tr></tbody>
</table></div>
<p class="since">Since 1.6</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-pop-source"></a><h3>cogl_pop_source ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_pop_source (<em class="parameter"><code><span class="type">void</span></code></em>);</pre>
<p>
Removes the material at the top of the source stack. The material
at the top of this stack defines the GPU state used to process
later primitives as defined by <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-set-source" title="cogl_set_source ()"><code class="function">cogl_set_source()</code></a>.
</p>
<p class="since">Since 1.6</p>
</div>
<hr>
<div class="refsect2">
<a name="COGL-TYPE-BUFFER-BIT:CAPS"></a><h3>COGL_TYPE_BUFFER_BIT</h3>
<pre class="programlisting">#define COGL_TYPE_BUFFER_BIT (cogl_buffer_bit_get_type())
</pre>
</div>
<hr>
<div class="refsect2">
<a name="cogl-clear"></a><h3>cogl_clear ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_clear (<em class="parameter"><code>const <a class="link" href="cogl-2.0-experimental-Color-Type.html#CoglColor" title="struct CoglColor"><span class="type">CoglColor</span></a> *color</code></em>,
<em class="parameter"><code><span class="type">unsigned long </span> buffers</code></em>);</pre>
<p>
Clears all the auxiliary buffers identified in the <em class="parameter"><code>buffers</code></em> mask, and if
that includes the color buffer then the specified <em class="parameter"><code>color</code></em> is used.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>color</code></em> :</span></p></td>
<td>Background color to clear to</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>buffers</code></em> :</span></p></td>
<td>A mask of <a class="link" href="cogl-2.0-experimental-Common-Types.html#CoglBufferBit" title="enum CoglBufferBit"><span class="type">CoglBufferBit</span></a>'s identifying which auxiliary
buffers to clear</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="CoglReadPixelsFlags"></a><h3>enum CoglReadPixelsFlags</h3>
<pre class="programlisting">typedef enum {
/*< prefix=COGL_READ_PIXELS >*/
COGL_READ_PIXELS_COLOR_BUFFER = 1L << 0
} CoglReadPixelsFlags;
</pre>
<p>
Flags for <a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#cogl-read-pixels" title="cogl_read_pixels ()"><code class="function">cogl_read_pixels()</code></a>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><a name="COGL-READ-PIXELS-COLOR-BUFFER:CAPS"></a><span class="term"><code class="literal">COGL_READ_PIXELS_COLOR_BUFFER</code></span></p></td>
<td>Read from the color buffer
</td>
</tr></tbody>
</table></div>
<p class="since">Since 1.0</p>
</div>
<hr>
<div class="refsect2">
<a name="cogl-read-pixels"></a><h3>cogl_read_pixels ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_read_pixels (<em class="parameter"><code><span class="type">int</span> x</code></em>,
<em class="parameter"><code><span class="type">int</span> y</code></em>,
<em class="parameter"><code><span class="type">int</span> width</code></em>,
<em class="parameter"><code><span class="type">int</span> height</code></em>,
<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-The-Top-Level-Context.html#CoglReadPixelsFlags" title="enum CoglReadPixelsFlags"><span class="type">CoglReadPixelsFlags</span></a> source</code></em>,
<em class="parameter"><code><a class="link" href="cogl-2.0-experimental-Common-Types.html#CoglPixelFormat" title="enum CoglPixelFormat"><span class="type">CoglPixelFormat</span></a> format</code></em>,
<em class="parameter"><code><span class="type">guint8</span> *pixels</code></em>);</pre>
<p>
This reads a rectangle of pixels from the current framebuffer where
position (0, 0) is the top left. The pixel at (x, y) is the first
read, and the data is returned with a rowstride of (width * 4).
</p>
<p>
Currently Cogl assumes that the framebuffer is in a premultiplied
format so if <em class="parameter"><code>format</code></em> is non-premultiplied it will convert it. To
read the pixel values without any conversion you should either
specify a format that doesn't use an alpha channel or use one of
the formats ending in PRE.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>x</code></em> :</span></p></td>
<td>The window x position to start reading from</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>y</code></em> :</span></p></td>
<td>The window y position to start reading from</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>width</code></em> :</span></p></td>
<td>The width of the rectangle you want to read</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>height</code></em> :</span></p></td>
<td>The height of the rectangle you want to read</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>source</code></em> :</span></p></td>
<td>Identifies which auxillary buffer you want to read
(only COGL_READ_PIXELS_COLOR_BUFFER supported currently)</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>format</code></em> :</span></p></td>
<td>The pixel format you want the result in
(only COGL_PIXEL_FORMAT_RGBA_8888 supported currently)</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>pixels</code></em> :</span></p></td>
<td>The location to write the pixel data.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="cogl-flush"></a><h3>cogl_flush ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> cogl_flush (<em class="parameter"><code><span class="type">void</span></code></em>);</pre>
<p>
This function should only need to be called in exceptional circumstances.
</p>
<p>
As an optimization Cogl drawing functions may batch up primitives
internally, so if you are trying to use raw GL outside of Cogl you stand a
better chance of being successful if you ask Cogl to flush any batched
geometry before making your state changes.
</p>
<p>
It only ensure that the underlying driver is issued all the commands
necessary to draw the batched primitives. It provides no guarantees about
when the driver will complete the rendering.
</p>
<p>
This provides no guarantees about the GL state upon returning and to avoid
confusing Cogl you should aim to restore any changes you make before
resuming use of Cogl.
</p>
<p>
If you are making state changes with the intention of affecting Cogl drawing
primitives you are 100% on your own since you stand a good chance of
conflicting with Cogl internals. For example clutter-gst which currently
uses direct GL calls to bind ARBfp programs will very likely break when Cogl
starts to use ARBfb programs itself for the material API.
</p>
<p class="since">Since 1.0</p>
</div>
</div>
</div>
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