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texture_filters: update ScaleForce (#5270)

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* texture_filters: update ScaleForce

* texture_filters: optimize scale_force

* texture_filters/scale_force: optimize final offset calculation
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Marshall Mohror 2020-04-27 23:50:47 -05:00 committed by GitHub
parent ed304e2877
commit 8a0b0c2fc7
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GPG key ID: 4AEE18F83AFDEB23
1 changed files with 69 additions and 44 deletions
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113
src/video_core/renderer_opengl/texture_filters/scale_force/scale_force.frag
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@ -1,7 +1,6 @@
//? #version 320 es
// from https://github.com/BreadFish64/ScaleFish/tree/master/scale_force
// shader adapted to GLSL 320 es and debugging outputs stripped
// MIT License
//
@ -27,15 +26,18 @@
precision mediump float;
in highp vec2 tex_coord;
in vec2 tex_coord;
out mediump vec4 frag_color;
out vec4 frag_color;
uniform sampler2D input_texture;
vec2 tex_size;
vec2 inv_tex_size;
vec4 cubic(float v) {
vec4 n = vec4(1.0, 2.0, 3.0, 4.0) - v;
vec4 s = n * n * n;
vec3 n = vec3(1.0, 2.0, 3.0) - v;
vec3 s = n * n * n;
float x = s.x;
float y = s.y - 4.0 * s.x;
float z = s.z - 4.0 * s.y + 6.0 * s.x;
@ -43,14 +45,11 @@ vec4 cubic(float v) {
return vec4(x, y, z, w) / 6.0;
}
vec4 textureBicubic(sampler2D sampler, vec2 tex_coords) {
vec2 tex_size = vec2(textureSize(sampler, 0));
vec2 inv_tex_size = 1.0 / tex_size;
// Bicubic interpolation
vec4 textureBicubic(vec2 tex_coords) {
tex_coords = tex_coords * tex_size - 0.5;
vec2 fxy = fract(tex_coords);
tex_coords -= fxy;
vec2 fxy = modf(tex_coords, tex_coords);
vec4 xcubic = cubic(fxy.x);
vec4 ycubic = cubic(fxy.y);
@ -62,10 +61,10 @@ vec4 textureBicubic(sampler2D sampler, vec2 tex_coords) {
offset *= inv_tex_size.xxyy;
vec4 sample0 = texture(sampler, offset.xz);
vec4 sample1 = texture(sampler, offset.yz);
vec4 sample2 = texture(sampler, offset.xw);
vec4 sample3 = texture(sampler, offset.yw);
vec4 sample0 = textureLod(input_texture, offset.xz, 0.0);
vec4 sample1 = textureLod(input_texture, offset.yz, 0.0);
vec4 sample2 = textureLod(input_texture, offset.xw, 0.0);
vec4 sample3 = textureLod(input_texture, offset.yw, 0.0);
float sx = s.x / (s.x + s.y);
float sy = s.z / (s.z + s.w);
@ -73,40 +72,66 @@ vec4 textureBicubic(sampler2D sampler, vec2 tex_coords) {
return mix(mix(sample3, sample2, sx), mix(sample1, sample0, sx), sy);
}
float ColorDist(vec4 a, vec4 b) {
mat4x3 center_matrix;
vec4 center_alpha;
// Finds the distance between four colors and cc in YCbCr space
vec4 ColorDist(vec4 A, vec4 B, vec4 C, vec4 D) {
// https://en.wikipedia.org/wiki/YCbCr#ITU-R_BT.2020_conversion
const vec3 K = vec3(0.2627, 0.6780, 0.0593);
const float luminance_weight = .6;
const mat3 MATRIX = mat3(K * luminance_weight, -.5 * K.r / (1.0 - K.b), -.5 * K.g / (1.0 - K.b),
.5, .5, -.5 * K.g / (1.0 - K.r), -.5 * K.b / (1.0 - K.r));
vec4 diff = a - b;
vec3 YCbCr = diff.rgb * MATRIX;
float d = length(YCbCr) * length(vec3(1.0)) / length(vec3(luminance_weight, 1.0, 1.0));
return sqrt(a.a * b.a * d * d + diff.a * diff.a);
}
const float LUMINANCE_WEIGHT = .6;
const mat3 YCBCR_MATRIX =
mat3(K * LUMINANCE_WEIGHT, -.5 * K.r / (1.0 - K.b), -.5 * K.g / (1.0 - K.b), .5, .5,
-.5 * K.g / (1.0 - K.r), -.5 * K.b / (1.0 - K.r));
const int radius = 2;
mat4x3 colors = mat4x3(A.rgb, B.rgb, C.rgb, D.rgb) - center_matrix;
mat4x3 YCbCr = YCBCR_MATRIX * colors;
vec4 color_dist = vec3(1.0) * YCbCr;
color_dist *= color_dist;
vec4 alpha = vec4(A.a, B.a, C.a, D.a);
return sqrt((color_dist + abs(center_alpha - alpha)) * alpha * center_alpha);
}
void main() {
vec2 input_size = vec2(textureSize(input_texture, 0));
vec4 center_texel = texture(input_texture, tex_coord);
vec2 final_offset = vec2(0.0);
float total_diff = 0.0;
vec4 bl = textureLodOffset(input_texture, tex_coord, 0.0, ivec2(-1, -1));
vec4 bc = textureLodOffset(input_texture, tex_coord, 0.0, ivec2(0, -1));
vec4 br = textureLodOffset(input_texture, tex_coord, 0.0, ivec2(1, -1));
vec4 cl = textureLodOffset(input_texture, tex_coord, 0.0, ivec2(-1, 0));
vec4 cc = textureLod(input_texture, tex_coord, 0.0);
vec4 cr = textureLodOffset(input_texture, tex_coord, 0.0, ivec2(1, 0));
vec4 tl = textureLodOffset(input_texture, tex_coord, 0.0, ivec2(-1, 1));
vec4 tc = textureLodOffset(input_texture, tex_coord, 0.0, ivec2(0, 1));
vec4 tr = textureLodOffset(input_texture, tex_coord, 0.0, ivec2(1, 1));
for (int y = -radius; y <= radius; ++y) {
for (int x = -radius; x <= radius; ++x) {
if (0 == (x | y))
continue;
vec2 offset = vec2(x, y);
float weight = pow(length(offset), -length(offset));
vec4 texel = texture(input_texture, tex_coord + offset / input_size);
float diff = ColorDist(texel, center_texel) * weight;
total_diff += diff;
final_offset += diff * offset;
}
tex_size = vec2(textureSize(input_texture, 0));
inv_tex_size = 1.0 / tex_size;
center_matrix = mat4x3(cc.rgb, cc.rgb, cc.rgb, cc.rgb);
center_alpha = cc.aaaa;
vec4 offset_tl = ColorDist(tl, tc, tr, cr);
vec4 offset_br = ColorDist(br, bc, bl, cl);
// Calculate how different cc is from the texels around it
float total_dist = dot(offset_tl + offset_br, vec4(1.0));
// Add together all the distances with direction taken into account
vec4 tmp = offset_tl - offset_br;
vec2 total_offset = tmp.wy + tmp.zz + vec2(-tmp.x, tmp.x);
if (total_dist == 0.0) {
// Doing bicubic filtering just past the edges where the offset is 0 causes black floaters
// and it doesn't really matter which filter is used when the colors aren't changing.
frag_color = cc;
} else {
// When the image has thin points, they tend to split apart.
// This is because the texels all around are different
// and total_offset reaches into clear areas.
// This works pretty well to keep the offset in bounds for these cases.
float clamp_val = length(total_offset) / total_dist;
vec2 final_offset = clamp(total_offset, -clamp_val, clamp_val) * inv_tex_size;
frag_color = textureBicubic(tex_coord - final_offset);
}
float clamp_val = length(final_offset) / total_diff;
final_offset = clamp(final_offset, -clamp_val, clamp_val);
frag_color = textureBicubic(input_texture, tex_coord - final_offset / input_size);
}