gtk/gsk/vulkan/resources/rounded-rect.glsl
Matthias Clasen 900a4e4d31 gsk: Move shader resources
Move the resources of each renderer to its subdirectory.
We've previously done that for the ngl renderer, but it
is better to be consistent and do it for all the renderers.
2021-04-03 08:24:58 -04:00

70 lines
2.0 KiB
GLSL

#ifndef _ROUNDED_RECT_
#define _ROUNDED_RECT_
struct RoundedRect
{
vec4 bounds;
vec4 corner_widths;
vec4 corner_heights;
};
float
ellipsis_dist (vec2 p, vec2 radius)
{
vec2 p0 = p / radius;
vec2 p1 = 2.0 * p0 / radius;
return (dot(p0, p0) - 1.0) / length (p1);
}
float
ellipsis_coverage (vec2 point, vec2 center, vec2 radius)
{
float d = ellipsis_dist (point - center, radius);
return clamp (0.5 - d, 0.0, 1.0);
}
float
rounded_rect_coverage (RoundedRect r, vec2 p)
{
if (p.x < r.bounds.x || p.y < r.bounds.y ||
p.x >= r.bounds.z || p.y >= r.bounds.w)
return 0.0;
vec2 rad_tl = vec2(r.corner_widths.x, r.corner_heights.x);
vec2 rad_tr = vec2(r.corner_widths.y, r.corner_heights.y);
vec2 rad_br = vec2(r.corner_widths.z, r.corner_heights.z);
vec2 rad_bl = vec2(r.corner_widths.w, r.corner_heights.w);
vec2 ref_tl = r.bounds.xy + vec2( r.corner_widths.x, r.corner_heights.x);
vec2 ref_tr = r.bounds.zy + vec2(-r.corner_widths.y, r.corner_heights.y);
vec2 ref_br = r.bounds.zw + vec2(-r.corner_widths.z, -r.corner_heights.z);
vec2 ref_bl = r.bounds.xw + vec2( r.corner_widths.w, -r.corner_heights.w);
float d_tl = ellipsis_coverage(p, ref_tl, rad_tl);
float d_tr = ellipsis_coverage(p, ref_tr, rad_tr);
float d_br = ellipsis_coverage(p, ref_br, rad_br);
float d_bl = ellipsis_coverage(p, ref_bl, rad_bl);
vec4 corner_coverages = 1.0 - vec4(d_tl, d_tr, d_br, d_bl);
bvec4 is_out = bvec4(p.x < ref_tl.x && p.y < ref_tl.y,
p.x > ref_tr.x && p.y < ref_tr.y,
p.x > ref_br.x && p.y > ref_br.y,
p.x < ref_bl.x && p.y > ref_bl.y);
return 1.0 - dot(vec4(is_out), corner_coverages);
}
RoundedRect
rounded_rect_shrink (RoundedRect r, vec4 amount)
{
vec4 new_bounds = r.bounds + vec4(1.0,1.0,-1.0,-1.0) * amount.wxyz;
vec4 new_widths = max (r.corner_widths - amount.wyyw, 0.0);
vec4 new_heights = max (r.corner_heights - amount.xxzz, 0.0);
return RoundedRect (new_bounds, new_widths, new_heights);
}
#endif