texture_filters: update ScaleForce (#5270)
* texture_filters: update ScaleForce * texture_filters: optimize scale_force * texture_filters/scale_force: optimize final offset calculation
This commit is contained in:
parent
ed304e2877
commit
8a0b0c2fc7
@ -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;
|
||||
}
|
||||
}
|
||||
|
||||
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);
|
||||
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);
|
||||
}
|
||||
}
|
||||
|
Loading…
Reference in New Issue
Block a user