need_texture_combine_separate is moved to cogl-pipeline.c and renamed
to _cogl_pipeline_need_texture_combine_separate. The function is
needed by both the ARBfp and GLSL codegen backends so it makes sense to
share it.
The code for finding the arbfp authority for a pipeline should be the
same as finding the GLSL authority. So that the code can be shared the
function has been moved to cogl-pipeline.c and renamed to
_cogl_pipeline_find_codegen_authority.
Only one of the material backends can be generating code at the same
time so it seems to make sense to share the same source buffer between
arbfp and glsl. The new name is fragment_source_buffer in case we
later want to create a new buffer for the vertex shader. That probably
couldn't share the same buffer because it will likely need to be
generated at the same time.
We now prepend a set of defines to any given GLSL shader so that we can
define builtin uniforms/attributes within the "cogl" namespace that we
can use to provide compatibility across a range of the earlier versions
of GLSL.
This updates test-cogl-shader-glsl.c and test-shader.c so they no longer
needs to special case GLES vs GL when splicing together its shaders as
well as the blur, colorize and desaturate effects.
To get a feel for the new, portable uniform/attribute names here are the
defines for OpenGL vertex shaders:
#define cogl_position_in gl_Vertex
#define cogl_color_in gl_Color
#define cogl_tex_coord_in gl_MultiTexCoord0
#define cogl_tex_coord0_in gl_MultiTexCoord0
#define cogl_tex_coord1_in gl_MultiTexCoord1
#define cogl_tex_coord2_in gl_MultiTexCoord2
#define cogl_tex_coord3_in gl_MultiTexCoord3
#define cogl_tex_coord4_in gl_MultiTexCoord4
#define cogl_tex_coord5_in gl_MultiTexCoord5
#define cogl_tex_coord6_in gl_MultiTexCoord6
#define cogl_tex_coord7_in gl_MultiTexCoord7
#define cogl_normal_in gl_Normal
#define cogl_position_out gl_Position
#define cogl_point_size_out gl_PointSize
#define cogl_color_out gl_FrontColor
#define cogl_tex_coord_out gl_TexCoord
#define cogl_modelview_matrix gl_ModelViewMatrix
#define cogl_modelview_projection_matrix gl_ModelViewProjectionMatrix
#define cogl_projection_matrix gl_ProjectionMatrix
#define cogl_texture_matrix gl_TextureMatrix
And for fragment shaders we have:
#define cogl_color_in gl_Color
#define cogl_tex_coord_in gl_TexCoord
#define cogl_color_out gl_FragColor
#define cogl_depth_out gl_FragDepth
#define cogl_front_facing gl_FrontFacing
This applies an API naming change that's been deliberated over for a
while now which is to rename CoglMaterial to CoglPipeline.
For now the new pipeline API is marked as experimental and public
headers continue to talk about materials not pipelines. The CoglMaterial
API is now maintained in terms of the cogl_pipeline API internally.
Currently this API is targeting Cogl 2.0 so we will have time to
integrate it properly with other upcoming Cogl 2.0 work.
The basic reasons for the rename are:
- That the term "material" implies to many people that they are
constrained to fragment processing; perhaps as some kind of high-level
texture abstraction.
- In Clutter they get exposed by ClutterTexture actors which may be
re-inforcing this misconception.
- When comparing how other frameworks use the term material, a material
sometimes describes a multi-pass fragment processing technique which
isn't the case in Cogl.
- In code, "CoglPipeline" will hopefully be a much more self documenting
summary of what these objects represent; a full GPU pipeline
configuration including, for example, vertex processing, fragment
processing and blending.
- When considering the API documentation story, at some point we need a
document introducing developers to how the "GPU pipeline" works so it
should become intuitive that CoglPipeline maps back to that
description of the GPU pipeline.
- This is consistent in terminology and concept to OpenGL 4's new
pipeline object which is a container for program objects.
Note: The cogl-material.[ch] files have been renamed to
cogl-material-compat.[ch] because otherwise git doesn't seem to treat
the change as a moving the old cogl-material.c->cogl-pipeline.c and so
we loose all our git-blame history.
