From 8a0b0c2fc7883a45492a3248b04a4ca48585a427 Mon Sep 17 00:00:00 2001 From: Marshall Mohror Date: Mon, 27 Apr 2020 23:50:47 -0500 Subject: [PATCH] texture_filters: update ScaleForce (#5270) * texture_filters: update ScaleForce * texture_filters: optimize scale_force * texture_filters/scale_force: optimize final offset calculation --- .../scale_force/scale_force.frag | 113 +++++++++++------- 1 file changed, 69 insertions(+), 44 deletions(-) diff --git a/src/video_core/renderer_opengl/texture_filters/scale_force/scale_force.frag b/src/video_core/renderer_opengl/texture_filters/scale_force/scale_force.frag index 884723487..f162278a5 100644 --- a/src/video_core/renderer_opengl/texture_filters/scale_force/scale_force.frag +++ b/src/video_core/renderer_opengl/texture_filters/scale_force/scale_force.frag @@ -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); }