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Diffstat (limited to 'src/gallium/docs/source/cso')
| -rw-r--r-- | src/gallium/docs/source/cso/rasterizer.rst | 123 |
1 files changed, 94 insertions, 29 deletions
diff --git a/src/gallium/docs/source/cso/rasterizer.rst b/src/gallium/docs/source/cso/rasterizer.rst index afb58ea375..4d8e1708e7 100644 --- a/src/gallium/docs/source/cso/rasterizer.rst +++ b/src/gallium/docs/source/cso/rasterizer.rst @@ -3,58 +3,123 @@ Rasterizer ========== -The rasterizer is the main chunk of state controlling how vertices are -interpolated into fragments. +The rasterizer state controls the rendering of points, lines and triangles. +Attributes include polygon culling state, line width, line stipple, +multisample state, scissoring and flat/smooth shading. + Members ------- -XXX undocumented light_twoside, front_winding, cull_mode, fill_cw, fill_ccw, offset_cw, offset_ccw -XXX moar undocumented poly_smooth, line_stipple_factor, line_last_pixel, offset_units, offset_scale -XXX sprite_coord_mode - flatshade If set, the provoking vertex of each polygon is used to determine the - color of the entire polygon. If not set, the color fragments will be - interpolated from each vertex's color. -scissor - Whether the scissor test is enabled. + color of the entire polygon. If not set, fragment colors will be + interpolated between the vertex colors. + Note that this is separate from the fragment shader input attributes + CONSTANT, LINEAR and PERSPECTIVE. We need the flatshade state at + clipping time to determine how to set the color of new vertices. + Also note that the draw module can implement flat shading by copying + the provoking vertex color to all the other vertices in the primitive. + +flatshade_first + Whether the first vertex should be the provoking vertex, for most + primitives. If not set, the last vertex is the provoking vertex. + +light_twoside + If set, there are per-vertex back-facing colors. The draw module + uses this state along with the front/back information to set the + final vertex colors prior to rasterization. + +front_winding + Indicates the window order of front-facing polygons, either + PIPE_WINDING_CW or PIPE_WINDING_CCW +cull_mode + Indicates which polygons to cull, either PIPE_WINDING_NONE (cull no + polygons), PIPE_WINDING_CW (cull clockwise-winding polygons), + PIPE_WINDING_CCW (cull counter clockwise-winding polygons), or + PIPE_WINDING_BOTH (cull all polygons). + +fill_cw + Indicates how to fill clockwise polygons, either PIPE_POLYGON_MODE_FILL, + PIPE_POLYGON_MODE_LINE or PIPE_POLYGON_MODE_POINT. +fill_ccw + Indicates how to fill counter clockwise polygons, either + PIPE_POLYGON_MODE_FILL, PIPE_POLYGON_MODE_LINE or PIPE_POLYGON_MODE_POINT. + poly_stipple_enable Whether polygon stippling is enabled. +poly_smooth + Controls OpenGL-style polygon smoothing/antialiasing +offset_cw + If set, clockwise polygons will have polygon offset factors applied +offset_ccw + If set, counter clockwise polygons will have polygon offset factors applied +offset_units + Specifies the polygon offset bias +offset_scale + Specifies the polygon offset scale + +line_width + The width of lines. +line_smooth + Whether lines should be smoothed. Line smoothing is simply anti-aliasing. +line_stipple_enable + Whether line stippling is enabled. +line_stipple_pattern + 16-bit bitfield of on/off flags, used to pattern the line stipple. +line_stipple_factor + When drawinga stippled line, each bit in the stipple pattern is + repeated N times, where N = line_stipple_factor + 1. +line_last_pixel + Controls whether the last pixel in a line is drawn or not. OpenGL + omits the last pixel to avoid double-drawing pixels at the ends of lines + when drawing connected lines. + point_smooth Whether points should be smoothed. Point smoothing turns rectangular points into circles or ovals. -point_sprite - Whether point sprites are enabled. 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_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). + For PIPE_SPRITE_COORD_UPPER_LEFT, the upper-left vertex will have + coordinate (0,0,0,1). + This state is needed by the 'draw' module because that's where each + point vertex is converted into four quad vertices. There's no other + place to emit the new vertex texture coordinates which are required for + 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. + +scissor + Whether the scissor test is enabled. + multisample Whether :ref:`MSAA` is enabled. -line_smooth - Whether lines should be smoothed. Line smoothing is simply anti-aliasing. -line_stipple_enable - Whether line stippling is enabled. -line_stipple_pattern - 16-bit bitfield of on/off flags, used to pattern the line stipple. + bypass_vs_clip_and_viewport Whether the entire TCL pipeline should be bypassed. This implies that vertices are pre-transformed for the viewport, and will not be run through the vertex shader. Note that implementations may still clip away vertices that are not in the viewport. -flatshade_first - Whether the first vertex should be the provoking vertex, for most - primitives. If not set, the last vertex is the provoking vertex. + gl_rasterization_rules Whether the rasterizer should use (0.5, 0.5) pixel centers. When not set, the rasterizer will use (0, 0) for pixel centers. -line_width - The width of lines. -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. + Notes ----- |