Document rasterizer.

src/gallium/docs/source/cso/rasterizer.rst

@@ -7,4 +7,78 @@ interpolated into fragments.
 Members
 -------
 
-XXX
+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.
+poly_stipple_enable
+    Whether polygon stippling is enabled.
+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.
+multisample
+    Whether 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
+-----
+
+flatshade
+^^^^^^^^^
+
+The actual interpolated shading algorithm is obviously
+implementation-dependent, but will usually be Gourard for most hardware.
+
+bypass_vs_clip_and_viewport
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+When set, 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 visible.
+
+flatshade_first
+^^^^^^^^^^^^^^^
+
+There are several important exceptions to the specification of this rule.
+
+* PIPE_PRIMITIVE_POLYGON: The provoking vertex is always the first vertex.
+  If the caller wishes to change the provoking vertex, they merely need to
+  rotate the vertices themselves.
+* PIPE_PRIMITIVE_QUAD, PIPE_PRIMITIVE_QUAD_STRIP: This option has no effect.
+* PIPE_PRIMITIVE_TRIANGLE_FAN: When set, the provoking vertex is the second
+  vertex, not the first. This permits each segment of the fan to have a
+  different color.