cairo-xcb is currently hitting an error when it tries to draw gradients with a single stop.
The RENDER specification doesn't say anything about conditions on the number of gradients stops, in particular it does not say that gradients with no stop at all or with just one stops will cause an error, but the server replies with a BadValue error whenever it receives a linear/radial gradient with nStops<2. http://cgit.freedesktop.org/xorg/proto/renderproto/plain/renderproto.txt http://cgit.freedesktop.org/xorg/xserver/tree/render/picture.c#n940 http://cgit.freedesktop.org/xorg/xserver/tree/render/picture.c#n981 Pixman allows gradients with a single stop (and their rasterization is just the same as if the stop was repeated twice at the same offset with the same components). cairo-xcb can be fixed to repeat the stop so that it will never ask for a single stop gradient, but we're currently trying to avoid workarounds in it, so we'd like the RENDER specification to be updated to state that they are prohibited or the code in xserver to actually allow them. Cairo never asks X to render a 0 stops gradient, but having the specification should probably define the behavior in this case as well. Andrea Canciani _______________________________________________ [email protected]: X.Org development Archives: http://lists.x.org/archives/xorg-devel Info: http://lists.x.org/mailman/listinfo/xorg-devel
