graphics: Fix screen filter calculation

This commit is contained in:
Hajime Hoshi 2018-02-24 04:25:07 +09:00
parent 9fba60ca03
commit af64f8689a

View File

@ -144,6 +144,7 @@ void main(void) {
#if defined(FILTER_SCREEN)
pos = roundTexel(pos);
highp vec2 texel_size = 1.0 / source_size;
pos -= texel_size / 2.0 / scale;
highp vec2 p0 = pos;
highp vec2 p1 = pos + texel_size / scale;
@ -153,7 +154,8 @@ void main(void) {
vec4 c3 = texture2D(texture, p1);
// Texels must be in the source rect, so it is not necessary to check that like linear filter.
vec2 rate = clamp((fract(pos * source_size) - vec2(0.5, 0.5)) * scale + vec2(0.5, 0.5), vec2(0.0, 0.), vec2(1.0, 1.0));
vec2 rateCenter = vec2(1.0, 1.0) - texel_size / 2.0 / scale;
vec2 rate = clamp(((fract(pos * source_size) - rateCenter) * scale) + rateCenter, 0.0, 1.0);
vec4 color = mix(mix(c0, c1, rate.x), mix(c2, c3, rate.x), rate.y);
#endif