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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 16:51:28 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 16:51:28 +0000
commit940b4d1848e8c70ab7642901a68594e8016caffc (patch)
treeeb72f344ee6c3d9b80a7ecc079ea79e9fba8676d /vcl/opengl/shaders/areaScaleFragmentShader.glsl
parentInitial commit. (diff)
downloadlibreoffice-upstream.tar.xz
libreoffice-upstream.zip
Adding upstream version 1:7.0.4.upstream/1%7.0.4upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'vcl/opengl/shaders/areaScaleFragmentShader.glsl')
-rw-r--r--vcl/opengl/shaders/areaScaleFragmentShader.glsl239
1 files changed, 239 insertions, 0 deletions
diff --git a/vcl/opengl/shaders/areaScaleFragmentShader.glsl b/vcl/opengl/shaders/areaScaleFragmentShader.glsl
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+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#version 130
+
+uniform sampler2D sampler;
+uniform int swidth;
+uniform int sheight;
+uniform float xscale;
+uniform float yscale;
+uniform float xoffset;
+uniform float yoffset;
+uniform float xfrompixelratio;
+uniform float yfrompixelratio;
+uniform float xtopixelratio;
+uniform float ytopixelratio;
+
+varying vec2 tex_coord;
+
+// This mode makes the scaling work like maskedTextureFragmentShader.glsl
+// (instead of like plain textureVertexShader.glsl).
+#ifdef MASKED
+varying vec2 mask_coord;
+uniform sampler2D mask;
+#endif
+
+#ifdef USE_REDUCED_REGISTER_VARIANT
+
+vec4 getTexel(int x, int y)
+{
+ vec2 pos = vec2( x * xfrompixelratio + xoffset, y * yfrompixelratio + yoffset );
+ vec4 texel = texture2D(sampler, pos);
+#ifdef MASKED
+ texel.a = 1.0 - texture2D(mask, pos - tex_coord.st + mask_coord.st).r;
+#endif
+ return texel;
+}
+
+void main(void)
+{
+ // Convert to pixel coordinates again.
+ int dx = int(( tex_coord.s - xoffset ) * xtopixelratio );
+ int dy = int(( tex_coord.t - yoffset ) * ytopixelratio );
+
+ // Compute the range of source pixels which will make up this destination pixel.
+ float fsx1 = min(dx * xscale, float(swidth - 1));
+ float fsx2 = min(fsx1 + xscale, float(swidth - 1));
+
+ float fsy1 = min(dy * yscale, float(sheight - 1));
+ float fsy2 = min(fsy1 + yscale, float(sheight - 1));
+
+ // To whole pixel coordinates.
+ int xstart = int(floor(fsx1));
+ int xend = int(floor(fsx2));
+
+ int ystart = int(floor(fsy1));
+ int yend = int(floor(fsy2));
+
+ float xlength = fsx2 - fsx1;
+ float ylength = fsy2 - fsy1;
+
+ float xContribution[3];
+ xContribution[0] = (1.0 - max(0.0, fsx1 - xstart)) / xlength;
+ xContribution[1] = 1.0 / xlength;
+ xContribution[2] = (1.0 - max(0.0, (xend + 1) - fsx2)) / xlength;
+
+ float yContribution[3];
+ yContribution[0] = (1.0 - max(0.0, fsy1 - ystart)) / ylength;
+ yContribution[1] = 1.0 / ylength;
+ yContribution[2] = (1.0 - max(0.0, (yend + 1) - fsy2)) / ylength;
+
+ vec4 sumAll = vec4(0.0, 0.0, 0.0, 0.0);
+ vec4 texel;
+ // First Y pass
+ {
+ vec4 sumX = vec4(0.0, 0.0, 0.0, 0.0);
+
+ sumX += getTexel(xstart, ystart) * xContribution[0];
+ for (int x = xstart + 1; x < xend; ++x)
+ {
+ sumX += getTexel(x, ystart) * xContribution[1];
+ }
+ sumX += getTexel(xend, ystart) * xContribution[2];
+
+ sumAll += sumX * yContribution[0];
+ }
+
+ // Middle Y Passes
+ for (int y = ystart + 1; y < yend; ++y)
+ {
+ vec4 sumX = vec4(0.0, 0.0, 0.0, 0.0);
+
+ sumX += getTexel(xstart, y) * xContribution[0];
+ for (int x = xstart + 1; x < xend; ++x)
+ {
+ sumX += getTexel(x, y) * xContribution[1];
+ }
+ sumX += getTexel(xend, y) * xContribution[2];
+
+ sumAll += sumX * yContribution[1];
+ }
+
+ // Last Y pass
+ {
+ vec4 sumX = vec4(0.0, 0.0, 0.0, 0.0);
+
+ sumX += getTexel(xstart, yend) * xContribution[0];
+ for (int x = xstart + 1; x < xend; ++x)
+ {
+ sumX += getTexel(x, yend) * xContribution[1];
+ }
+ sumX += getTexel(xend, yend) * xContribution[2];
+
+ sumAll += sumX * yContribution[2];
+ }
+
+ gl_FragColor = sumAll;
+}
+#else
+void main(void)
+{
+ // Convert to pixel coordinates again.
+ int dx = int(( tex_coord.s - xoffset ) * xtopixelratio );
+ int dy = int(( tex_coord.t - yoffset ) * ytopixelratio );
+
+ // How much each column/row will contribute to the resulting pixel.
+ // Note: These values are always the same for the same X (or Y),
+ // so they could be precalculated in C++ and passed to the shader,
+ // but GLSL has limits on the size of uniforms passed to it,
+ // so it'd need something like texture buffer objects from newer
+ // GLSL versions, and it seems the hassle is not really worth it.
+ float xratio[ 16 + 2 ];
+ float yratio[ 16 + 2 ];
+
+ // For finding the first and last source pixel.
+ int xpixel[ 16 + 2 ];
+ int ypixel[ 16 + 2 ];
+
+ int xpos = 0;
+ int ypos = 0;
+
+ // Compute the range of source pixels which will make up this destination pixel.
+ float fsx1 = dx * xscale;
+ float fsx2 = fsx1 + xscale;
+ // To whole pixel coordinates.
+ int sx1 = int( ceil( fsx1 ) );
+ int sx2 = int( floor( fsx2 ) );
+ // Range checking.
+ sx2 = min( sx2, swidth - 1 );
+ sx1 = min( sx1, sx2 );
+
+ // How much one full column contributes to the resulting pixel.
+ float width = min( xscale, swidth - fsx1 );
+
+ if( sx1 - fsx1 > 0.001 )
+ { // The first column contributes only partially.
+ xpixel[ xpos ] = sx1 - 1;
+ xratio[ xpos ] = ( sx1 - fsx1 ) / width;
+ ++xpos;
+ }
+ for( int sx = sx1; sx < sx2; ++sx )
+ { // Columns that fully contribute to the resulting pixel.
+ xpixel[ xpos ] = sx;
+ xratio[ xpos ] = 1.0 / width;
+ ++xpos;
+ }
+ if( fsx2 - sx2 > 0.001 )
+ { // The last column contributes only partially.
+ xpixel[ xpos ] = sx2;
+ xratio[ xpos ] = min( min( fsx2 - sx2, 1.0 ) / width, 1.0 );
+ ++xpos;
+ }
+
+ // The same for Y.
+ float fsy1 = dy * yscale;
+ float fsy2 = fsy1 + yscale;
+ int sy1 = int( ceil( fsy1 ) );
+ int sy2 = int( floor( fsy2 ) );
+ sy2 = min( sy2, sheight - 1 );
+ sy1 = min( sy1, sy2 );
+
+ float height = min( yscale, sheight - fsy1 );
+
+ if( sy1 - fsy1 > 0.001 )
+ {
+ ypixel[ ypos ] = sy1 - 1;
+ yratio[ ypos ] = ( sy1 - fsy1 ) / height;
+ ++ypos;
+ }
+ for( int sy = sy1; sy < sy2; ++sy )
+ {
+ ypixel[ ypos ] = sy;
+ yratio[ ypos ] = 1.0 / height;
+ ++ypos;
+ }
+ if( fsy2 - sy2 > 0.001 )
+ {
+ ypixel[ ypos ] = sy2;
+ yratio[ ypos ] = min( min( fsy2 - sy2, 1.0 ) / height, 1.0 );
+ ++ypos;
+ }
+
+ int xstart = xpixel[ 0 ];
+ int xend = xpixel[ xpos - 1 ];
+ int ystart = ypixel[ 0 ];
+ int yend = ypixel[ ypos - 1 ];
+
+ vec4 sum = vec4( 0.0, 0.0, 0.0, 0.0 );
+
+ ypos = 0;
+ for( int y = ystart; y <= yend; ++y, ++ypos )
+ {
+ vec4 tmp = vec4( 0.0, 0.0, 0.0, 0.0 );
+ xpos = 0;
+ for( int x = xstart; x <= xend; ++x, ++xpos )
+ {
+ vec2 pos = vec2( x * xfrompixelratio + xoffset, y * yfrompixelratio + yoffset );
+#ifndef MASKED
+ tmp += texture2D( sampler, pos ) * xratio[ xpos ];
+#else
+ vec4 texel;
+ texel = texture2D( sampler, pos );
+ texel.a = 1.0 - texture2D( mask, pos - tex_coord.st + mask_coord.st ).r;
+ tmp += texel * xratio[ xpos ];
+#endif
+ }
+ sum += tmp * yratio[ ypos ];
+ }
+
+ gl_FragColor = sum;
+}
+#endif
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */