Removed the drop and create from the ComponentVTable:
since we are not using VBox<ComponentVTable>, this simplifies a bit
the code of the interpreter and everything else.
But there is still a lot of changes everywhere to support that the Component
is pinned.
This is just for the component. Which would be required if later we want
to access the properties as Pin<Property<_>>. But we have not yet ability
to do projections
This introduces a separate rendering preparation step in the main
window. As a consequence, the component becomes a parameter and the
graphicstest example can't use the main window anymore.
The decision whether a new low-level primitive needs to be created or
not is made by comparing the last RenderingPrimitive against the new
one.
On the upside, this means that property changes are now reflected in the
graphics.
This shall become the successor to RenderingInfo. For now it's just a
place holder, but the idea is that backend creates the opaque primitive
that holds this public rendering primitive, exposed via the
HasRenderingPrimitive trait.
Rename the backend specific RenderingPrimitive to LowLevelRenderingPrimitive,
in order to make room for a high-level RenderingPrimitive enum that's public.
Forward the text and color properties to the rendering backend, where
right now we just rendering all the glyphs into a dedicated texture.
Next steps are a glyph atlas texture, blending the specified color with
the alpha of the glyphs, configurable size and family, shaping with
Harfbuzz and may more things.
Make our GL context not current when done with the initialization
and make it current for the duration fo primitive creation and frame
rendering.
Fixes#4
These are the basics. Still to do are fixing the alpha channel blending, the rect handling,
a texture type to avoid consuming the image over and over again. And more :-)
The idea is that they can be recursively rendered and propagate at least
the transform but also clip in the future.
One thing that's left is to split RenderNode into RenderNode and
RenderNodeMut, so that the rendering itself can be done on a non-mutable
tree reference.
