PresentParams

The CPU copy of the std140 `Params` block in present.frag.

In the namespace rhi. Declared in src/libs/librhiwidget/rhi/PresentParams.hpp.

Detailed description

Every member is 4 bytes and each vec4/vec2 starts on its std140 alignment, so the struct has no padding and is uploaded as it is. Keep the member order and types the same as the block in librhiwidget/rhi/shaders/present.frag; the static_asserts below pin the offsets. RhiPresentWidget fills it, and so does any test that draws the real present quad, so the layout is written down once.

80 bytes: std140 rounds a uniform block up to 16 bytes, and the fifth row holds one flag and three reserved words.