pub const RADIUS_UNIFORM: &str = "corner_radius";Expand description
The four corner radii a rounded-corner program takes, in physical
pixels, packed (top_left, top_right, bottom_left, bottom_right).
Effect::radii is in logical pixels, and this is the other side of
that seam. A style says radius: 12 because that is what someone types
into a Pane.qml, and a style should not have to know a monitor’s scale;
the shader measures in texture pixels throughout and knows nothing else.
Whoever sets this uniform does the multiply by the output scale, on all
four – crates/solium/src/pass.rs, not this crate and not the shader.
The two numbers are equal on a scale-1 output, which is why getting it
wrong looks perfect on the machine it was written on and shows up only on
a HiDPI screen.