| '''OpenGL extension NV.instanced_arrays |
| |
| This module customises the behaviour of the |
| OpenGL.raw.GLES2.NV.instanced_arrays to provide a more |
| Python-friendly API |
| |
| Overview (from the spec) |
| |
| A common use case in GL for some applications is to be able to |
| draw the same object, or groups of similar objects that share |
| vertex data, primitive count and type, multiple times. This |
| extension provides a means of accelerating such use cases while |
| limiting the number of required API calls, and keeping the amount |
| of duplicate data to a minimum. |
| |
| In particular, this extension specifies an alternative to the |
| read-only shader variable introduced by NV_draw_instanced. It |
| uses the same draw calls introduced by that extension, but |
| redefines them so that a vertex shader can instead use vertex |
| array attributes as a source of instance data. |
| |
| This extension introduces an array "divisor" for generic |
| vertex array attributes, which when non-zero specifies that the |
| attribute is "instanced." An instanced attribute does not |
| advance per-vertex as usual, but rather after every <divisor> |
| conceptual draw calls. |
| |
| (Attributes which aren't instanced are repeated in their entirety |
| for every conceptual draw call.) |
| |
| By specifying transform data in an instanced attribute or series |
| of instanced attributes, vertex shaders can, in concert with the |
| instancing draw calls, draw multiple instances of an object with |
| one draw call. |
| |
| The official definition of this extension is available here: |
| http://www.opengl.org/registry/specs/NV/instanced_arrays.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.NV.instanced_arrays import * |
| from OpenGL.raw.GLES2.NV.instanced_arrays import _EXTENSION_NAME |
|
|
| def glInitInstancedArraysNV(): |
| '''Return boolean indicating whether this extension is available''' |
| from OpenGL import extensions |
| return extensions.hasGLExtension( _EXTENSION_NAME ) |
|
|
|
|
| |
