diff options
Diffstat (limited to 'src/gallium/docs')
| -rw-r--r-- | src/gallium/docs/source/cso/rasterizer.rst | 32 | ||||
| -rw-r--r-- | src/gallium/docs/source/tgsi.rst | 6 |
2 files changed, 23 insertions, 15 deletions
diff --git a/src/gallium/docs/source/cso/rasterizer.rst b/src/gallium/docs/source/cso/rasterizer.rst index bfa4a1170a2..24cc78c68de 100644 --- a/src/gallium/docs/source/cso/rasterizer.rst +++ b/src/gallium/docs/source/cso/rasterizer.rst @@ -119,18 +119,20 @@ point_size_per_vertex Whether vertices have a point size element. point_size The size of points, if not specified per-vertex. -point_size_min - The minimum size of points. -point_size_max - The maximum size of points. -point_sprite - Whether points are drawn as sprites (textured quads) +sprite_coord_enable + Specifies if a coord has its texture coordinates replaced or not. This + is a packed bitfield containing the enable for all coords - if all are 0 + point sprites are effectively disabled, though points may still be + rendered slightly different according to point_quad_rasterization. + If any coord is non-zero, point_smooth should be disabled, and + point_quad_rasterization enabled. + If enabled, the four vertices of the resulting quad will be assigned + texture coordinates, according to sprite_coord_mode. sprite_coord_mode Specifies how the value for each shader output should be computed when - drawing sprites. If PIPE_SPRITE_COORD_NONE, don't change the vertex - shader output. Otherwise, the four vertices of the resulting quad will - be assigned texture coordinates. For PIPE_SPRITE_COORD_LOWER_LEFT, the - lower left vertex will have coordinate (0,0,0,1). + drawing sprites, for each coord which has sprite_coord_enable set. + For PIPE_SPRITE_COORD_LOWER_LEFT, the lower left vertex will have + coordinate (0,0,0,1). For PIPE_SPRITE_COORD_UPPER_LEFT, the upper-left vertex will have coordinate (0,0,0,1). This state is needed by :ref:`Draw` because that's where each @@ -139,7 +141,15 @@ sprite_coord_mode sprite rendering. Note that when geometry shaders are available, this state could be removed. A special geometry shader defined by the state tracker could - converts the incoming points into quads with the proper texture coords. + convert the incoming points into quads with the proper texture coords. +point_quad_rasterization + This determines if points should be rasterized as quads or points. + d3d always uses quad rasterization for points, regardless if point sprites + are enabled or not, but OGL has different rules. If point_quad_rasterization + is set, point_smooth should be disabled, and points will be rendered as + squares even if multisample is enabled. + sprite_coord_enable should be zero if point_quad_rasterization is not + enabled. scissor Whether the scissor test is enabled. diff --git a/src/gallium/docs/source/tgsi.rst b/src/gallium/docs/source/tgsi.rst index fc5482d3842..c292cd37d5c 100644 --- a/src/gallium/docs/source/tgsi.rst +++ b/src/gallium/docs/source/tgsi.rst @@ -1380,10 +1380,8 @@ TGSI_SEMANTIC_PSIZE """"""""""""""""""" PSIZE, or point size, is used to specify point sizes per-vertex. It should -be in ``(p, n, x, f)`` format, where ``p`` is the point size, ``n`` is the minimum -size, ``x`` is the maximum size, and ``f`` is the fade threshold. - -XXX this is arb_vp. is this what we actually do? should double-check... +be in ``(s, 0, 0, 1)`` format, where ``s`` is the (possibly clamped) point size. +Only the first component matters when writing from the vertex shader. When using this semantic, be sure to set the appropriate state in the :ref:`rasterizer` first. |