| '''OpenGL extension OES.sample_variables |
| |
| This module customises the behaviour of the |
| OpenGL.raw.GLES2.OES.sample_variables to provide a more |
| Python-friendly API |
| |
| Overview (from the spec) |
| |
| This extension allows fragment shaders more control over multisample |
| rendering. The mask of samples covered by a fragment can be read by |
| the shader and individual samples can be masked out. Additionally |
| fragment shaders can be run on individual samples and the sample's |
| ID and position read to allow better interaction with multisample |
| resources such as textures. |
| |
| In multisample rendering, an implementation is allowed to assign the |
| same sets of fragment shader input values to each sample, which then |
| allows the optimization where the shader is only evaluated once and |
| then distributed to the samples that have been determined to be |
| covered by the primitive currently being rasterized. This extension |
| does not change how values are interpolated, but it makes some details |
| of the current sample available. This means that where these features |
| are used (gl_SampleID and gl_SamplePosition), implementations must |
| run the fragment shader for each sample. |
| |
| In order to obtain per-sample interpolation on fragment inputs, either |
| OES_sample_shading or OES_shader_multisample_interpolation must |
| be used in conjunction with the features from this extension. |
| |
| The official definition of this extension is available here: |
| http://www.opengl.org/registry/specs/OES/sample_variables.txt |
| ''' |
| from OpenGL import platform, constant, arrays |
| from OpenGL import extensions, wrapper |
| import ctypes |
| from OpenGL.raw.GLES2 import _types, _glgets |
| from OpenGL.raw.GLES2.OES.sample_variables import * |
| from OpenGL.raw.GLES2.OES.sample_variables import _EXTENSION_NAME |
|
|
| def glInitSampleVariablesOES(): |
| '''Return boolean indicating whether this extension is available''' |
| from OpenGL import extensions |
| return extensions.hasGLExtension( _EXTENSION_NAME ) |
|
|
|
|
| |
