Files
panopainter/data/shaders/texture-mask.glsl
2019-05-17 11:21:50 +02:00

44 lines
1.2 KiB
GLSL

[[vertex]]
uniform mat4 mvp;
in vec4 pos;
in vec2 uvs;
out vec2 uv;
void main()
{
uv = uvs;
gl_Position = mvp * vec4(pos.xyz, 1.0);
}
[[fragment]]
uniform sampler2D tex;
uniform vec2 pattern_offset;
in mediump vec2 uv;
out mediump vec4 frag;
void main()
{
int zero_count = 0;
if (textureOffset(tex, uv, ivec2(-1, -1)).r > 0.99) zero_count++;
if (textureOffset(tex, uv, ivec2(-1, 0)).r > 0.99) zero_count++;
if (textureOffset(tex, uv, ivec2(-1, +1)).r > 0.99) zero_count++;
if (textureOffset(tex, uv, ivec2( 0, -1)).r > 0.99) zero_count++;
if (textureOffset(tex, uv, ivec2( 0, 0)).r > 0.99) zero_count++;
if (textureOffset(tex, uv, ivec2( 0, +1)).r > 0.99) zero_count++;
if (textureOffset(tex, uv, ivec2(+1, -1)).r > 0.99) zero_count++;
if (textureOffset(tex, uv, ivec2(+1, 0)).r > 0.99) zero_count++;
if (textureOffset(tex, uv, ivec2(+1, +1)).r > 0.99) zero_count++;
mediump float edge = (zero_count > 1 && zero_count < 8) ? 1.0 : 0.0;
const mediump vec4 c1 = vec4(1.0, 1.0, 1.0, 1.0);
const mediump vec4 c2 = vec4(0.9, 0.9, 0.9, 1.0);
mediump vec2 c = floor(fract((uv + pattern_offset) * 50.0) * 2.0);
mediump float alpha = mix(c.x, 1.0 - c.x, c.y);
frag = vec4(vec3(edge * alpha), edge);
}