Add the cogl_point_coord snippet builtin

This adds a #define for gl_PointCoord to all shaders so that it can be
accessed with a name in the Cogl namespace.

Reviewed-by: Robert Bragg <robert@linux.intel.com>
(cherry picked from commit c28fc054788e88627bcc2346f4c4c368870ff777)
This commit is contained in:
Neil Roberts 2013-08-25 02:19:05 +01:00
parent cb178b7a3a
commit 4bc7377727
3 changed files with 17 additions and 2 deletions

View File

@ -66,7 +66,9 @@
"#define cogl_color_out gl_FragColor\n" \
"#define cogl_depth_out gl_FragDepth\n" \
"\n" \
"#define cogl_front_facing gl_FrontFacing\n"
"#define cogl_front_facing gl_FrontFacing\n" \
"\n" \
"#define cogl_point_coord gl_PointCoord\n"
#if 0
/* GLSL 1.2 has a bottom left origin, though later versions
* allow use of an origin_upper_left keyword which would be

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@ -279,6 +279,19 @@ COGL_BEGIN_DECLS
* coloring algorithms. This is equivalent to #gl_FrontFacing.
* </para></glossdef>
* </glossentry>
* <glossentry>
* <glossterm>vec2 <emphasis>cogl_point_coord</emphasis></glossterm>
* <glossdef><para>
* When rendering points, this will contain a vec2 which represents
* the position within the point of the current fragment.
* vec2(0.0,0.0) will be the topleft of the point and vec2(1.0,1.0)
* will be the bottom right. Note that there is currently a bug in
* Cogl where when rendering to an offscreen buffer these
* coordinates will be upside-down. The value is undefined when not
* rendering points. This builtin can only be used if the
* %COGL_FEATURE_ID_POINT_SPRITE feature is available.
* </para></glossdef>
* </glossentry>
* </glosslist>
*
* Here is an example of using a snippet to add a desaturate effect to the

View File

@ -421,7 +421,7 @@ ensure_texture_lookup_generated (CoglPipelineShaderState *shader_state,
if (cogl_pipeline_get_layer_point_sprite_coords_enabled (pipeline,
layer->index))
g_string_append_printf (shader_state->source,
"vec4 (gl_PointCoord, 0.0, 1.0)");
"vec4 (cogl_point_coord, 0.0, 1.0)");
else
g_string_append_printf (shader_state->source,
"cogl_tex_coord%i_in",