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Gecko:2DGraphicsSketch: Difference between revisions
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''This class is mostly stateless. The major piece of state is of course what we've rendered into the target. We also store a CTM and a current clip, since we often want to draw an arbitrary chunk of content with a given CTM and clip, and passing the CTM and clip around alongside the DrawTarget would be overly burdensome. But we give direct set/get access to the clip and matrix --- so no save/restore needed, and it'll be easy to set the clip to anything we want whenever we want.'' | ''This class is mostly stateless. The major piece of state is of course what we've rendered into the target. We also store a CTM and a current clip, since we often want to draw an arbitrary chunk of content with a given CTM and clip, and passing the CTM and clip around alongside the DrawTarget would be overly burdensome. But we give direct set/get access to the clip and matrix --- so no save/restore needed, and it'll be easy to set the clip to anything we want whenever we want.'' | ||
The primary drawing primitives correspond to cairo's fill, stroke, mask and show_glyphs --- except for no paint(). | The primary drawing primitives correspond to cairo's fill, stroke, mask and show_glyphs --- except for no paint(). It just doesn't seem useful. | ||
''We should also provide shortcuts that correspond to canvas-2D operations.'' This will offer maximum efficiency, so we don't have to spend cycles detecting special cases when the caller code already knows what the special case is. | ''We should also provide shortcuts that correspond to canvas-2D operations.'' This will offer maximum efficiency, so we don't have to spend cycles detecting special cases when the caller code already knows what the special case is. | ||