Because when mask depth is 1, there is no Anti-Alias at all,
in this case, the directly render can work well and it is faseter.
Signed-off-by: Junyan He <junyan.he@linux.intel.com>
We firstly get the render area by clipping the trapezoid
with the clip rect, then split the clipped area into small
triangles and use the composite logic to generate the result
directly. This manner is fast but have the problem that
some implementation of GL do not implement the Anti-Alias
of triangles fill, so the edge sometimes has sawtooth. It is
not acceptable when use trapezoid to approximate circles and
wide lines.
Signed-off-by: Junyan He <junyan.he@linux.intel.com>
We seperate the composite to two phases, firstly to
select the shader according to source type and logic
op, setting the right parameters. Then we emit the
vertex array to generate the dest result.
The reason why we do this is that the shader may be
used to composite no only rect, trapezoid and triangle
render function can also use it to render triangles and
polygens. The old function glamor_composite_with_shader
do the whole two phases work and can not match the
new request.
Signed-off-by: Junyan He <junyan.he@linux.intel.com>
The old manner of trapezoid render uses pixman to
generate a mask pixmap and upload it to the GPU.
This effect the performance. We now use shader to
generate the temp trapezoid mask to avoid the
uploading of this pixmap.
We implement a anti-alias manner in the shader
according to pixman, which will caculate the area
inside the trapezoid dividing total area for every
pixel and assign it to the alpha value of that pixel.
The pixman use a int-to-fix manner to approximate but
the shader use float, so the result may have some
difference.
Because the array in the shader has optimization problem,
we need to emit the vertex of every trapezoid every
time, which will effect the performance a lot. Need to
improve it.
Signed-off-by: Junyan He <junyan.he@linux.intel.com>
Create the file glamor_trapezoid.c, extract the logic
relating to trapezoid from glamor_render.c to this file.
Signed-off-by: Junyan He <junyan.he@linux.intel.com>
