Read-only mirror of https://gitlab.gnome.org/GNOME/mutter
fecaaea132
Instead of drawing paths using the stencil buffer trick, it now tesselates the path into triangles using the GLU tesselator and renders them directly. A vbo is created with one vertex for each node on the path. The tesselator is used to generate a series of indices into the vbo as triangles. The tesselator's output of strips and fans is converted into GL_TRIANGLES so that it can be rendered with a single draw call (but the vertices are still shared via the indices). The vbo is stored with the path so that if the application uses retained paths then Cogl won't have to tessellate again. The vertices also have texture coordinates associated with them so that it can replicate the old behaviour of drawing a material with a texture by fitting the texture to the bounding box of the path and then clipping it. However if the texture contains waste or is sliced then the vertex buffer code will refuse to draw it. In this case it will revert back to drawing the path into the stencil buffer and then drawing the material as a clipped quad. The VBO is used even when setting up the stencil buffer for clipping to a path because the tessellated geometry may cover less area. The old scanline rasterizer has been removed because the tesselator should work equally well on drivers with no stencil buffer. |
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| cogl | ||
| doc | ||
| pango | ||
| Makefile.am | ||