Performing a full-screen RenderPass resolve is too expensive.
Because most composite cases only require a small area to be rendered off-screen.
To improve performance, use the bounds of the Geometry for off-screen rendering whenever possible
A minor syntactic adjustment to two instances of operator== and one instance of operator!=, both to the end of ensuring these locally-scoped functions are properly identified as const. In the majority of cases, this shouldn't have any impact; however, this change makes these operators play nice in c++20 contexts.
* restrict the scissor box of composite task
* do not tessellate stroke or fill geometry if there is no Fill or
Stroke color
* use actually transformed curve to calculate polyline count when doing
curve flatten
* Support rendering Gradient in path Stroke mode
* Fix GlStencilCoverTask not support even-odd fill rule
* Make GlStencilCoverTask can discard overlapped area during stroke
rendering
* add new render task to do stencil and cover rendering which is a
fallback rendering method to handle cases that trianglation tessellation
failed
* add a new tessellator to generate stencil and cover vertex mesh
* Use uniform block to pack all color informations
* Move the actual gl draw call into GlRenderer::sync function, so all
data is been uploaded into GPU
* Make GlRenderTask simple and generic for direct gl draw
