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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/scale.cxx
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 '')
-rw-r--r--vcl/opengl/scale.cxx423
1 files changed, 423 insertions, 0 deletions
diff --git a/vcl/opengl/scale.cxx b/vcl/opengl/scale.cxx
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+++ b/vcl/opengl/scale.cxx
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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/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed
+ * with this work for additional information regarding copyright
+ * ownership. The ASF licenses this file to you under the Apache
+ * License, Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of
+ * the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <sal/config.h>
+#include <sal/log.hxx>
+
+#include <cmath>
+
+#include <vcl/opengl/OpenGLHelper.hxx>
+
+#include <vcl/bitmap.hxx>
+
+#include <opengl/zone.hxx>
+#include <opengl/salbmp.hxx>
+#include <opengl/program.hxx>
+#include <opengl/texture.hxx>
+#include <opengl/RenderState.hxx>
+
+#include <ResampleKernel.hxx>
+
+using vcl::Kernel;
+using vcl::Lanczos3Kernel;
+
+bool OpenGLSalBitmap::ImplScaleFilter(
+ const rtl::Reference< OpenGLContext > &xContext,
+ const double& rScaleX,
+ const double& rScaleY,
+ GLenum nFilter )
+{
+ OpenGLFramebuffer* pFramebuffer;
+ OpenGLProgram* pProgram;
+ GLenum nOldFilter;
+ int nNewWidth( mnWidth * rScaleX );
+ int nNewHeight( mnHeight * rScaleY );
+
+ pProgram = xContext->UseProgram( "textureVertexShader",
+ "textureFragmentShader" );
+ if( !pProgram )
+ return false;
+
+ OpenGLTexture aNewTex(nNewWidth, nNewHeight);
+ pFramebuffer = xContext->AcquireFramebuffer( aNewTex );
+
+ pProgram->SetTexture( "sampler", maTexture );
+ nOldFilter = maTexture.GetFilter();
+ maTexture.SetFilter( nFilter );
+ pProgram->ApplyMatrix(mnWidth, mnHeight);
+ pProgram->DrawTexture( maTexture );
+ maTexture.SetFilter( nOldFilter );
+ pProgram->Clean();
+
+ OpenGLContext::ReleaseFramebuffer( pFramebuffer );
+
+ mnWidth = nNewWidth;
+ mnHeight = nNewHeight;
+ maTexture = aNewTex;
+
+ CHECK_GL_ERROR();
+ return true;
+}
+
+void OpenGLSalBitmap::ImplCreateKernel(
+ const double& fScale,
+ const Kernel& rKernel,
+ GLfloat*& pWeights,
+ sal_uInt32& aKernelSize )
+{
+ const double fSamplingRadius(rKernel.GetWidth());
+ const double fScaledRadius((fScale < 1.0) ? fSamplingRadius / fScale : fSamplingRadius);
+ const double fFilterFactor(std::min(fScale, 1.0));
+ int aNumberOfContributions;
+ double aSum( 0 );
+
+ aNumberOfContributions = (static_cast< sal_uInt32 >(fabs(ceil(fScaledRadius))) * 2) + 1 - 6;
+ aKernelSize = aNumberOfContributions / 2 + 1;
+
+ // avoid a crash for now; re-think me.
+ if (aKernelSize > 16)
+ aKernelSize = 16;
+
+ pWeights = new GLfloat[16];
+ memset( pWeights, 0, 16 * sizeof( GLfloat ) );
+
+ for( sal_uInt32 i(0); i < aKernelSize; i++ )
+ {
+ const GLfloat aWeight( rKernel.Calculate( fFilterFactor * i ) );
+ if( fabs( aWeight ) >= 0.0001 )
+ {
+ pWeights[i] = aWeight;
+ aSum += i > 0 ? aWeight * 2 : aWeight;
+ }
+ }
+
+ for( sal_uInt32 i(0); i < aKernelSize; i++ )
+ {
+ pWeights[i] /= aSum;
+ }
+}
+
+bool OpenGLSalBitmap::ImplScaleConvolution(
+ const rtl::Reference< OpenGLContext > &xContext,
+ const double& rScaleX,
+ const double& rScaleY,
+ const Kernel& aKernel )
+{
+ OpenGLFramebuffer* pFramebuffer;
+ OpenGLProgram* pProgram;
+ GLfloat* pWeights( nullptr );
+ sal_uInt32 nKernelSize;
+ GLfloat aOffsets[32];
+ int nNewWidth( mnWidth * rScaleX );
+ int nNewHeight( mnHeight * rScaleY );
+
+ // TODO Make sure the framebuffer is alright
+
+ pProgram = xContext->UseProgram( "textureVertexShader",
+ "convolutionFragmentShader" );
+ if( pProgram == nullptr )
+ return false;
+
+ // horizontal scaling in scratch texture
+ if( mnWidth != nNewWidth )
+ {
+ OpenGLTexture aScratchTex(nNewWidth, nNewHeight);
+
+ pFramebuffer = xContext->AcquireFramebuffer( aScratchTex );
+
+ for( sal_uInt32 i = 0; i < 16; i++ )
+ {
+ aOffsets[i * 2] = i / static_cast<double>(mnWidth);
+ aOffsets[i * 2 + 1] = 0;
+ }
+ ImplCreateKernel( rScaleX, aKernel, pWeights, nKernelSize );
+ pProgram->SetUniform1fv( "kernel", 16, pWeights );
+ pProgram->SetUniform2fv( "offsets", 16, aOffsets );
+ pProgram->SetTexture( "sampler", maTexture );
+ pProgram->DrawTexture( maTexture );
+ pProgram->Clean();
+
+ maTexture = aScratchTex;
+ OpenGLContext::ReleaseFramebuffer( pFramebuffer );
+ }
+
+ // vertical scaling in final texture
+ if( mnHeight != nNewHeight )
+ {
+ OpenGLTexture aScratchTex(nNewWidth, nNewHeight);
+
+ pFramebuffer = xContext->AcquireFramebuffer( aScratchTex );
+
+ for( sal_uInt32 i = 0; i < 16; i++ )
+ {
+ aOffsets[i * 2] = 0;
+ aOffsets[i * 2 + 1] = i / static_cast<double>(mnHeight);
+ }
+ ImplCreateKernel( rScaleY, aKernel, pWeights, nKernelSize );
+ pProgram->SetUniform1fv( "kernel", 16, pWeights );
+ pProgram->SetUniform2fv( "offsets", 16, aOffsets );
+ pProgram->SetTexture( "sampler", maTexture );
+ pProgram->DrawTexture( maTexture );
+ pProgram->Clean();
+
+ maTexture = aScratchTex;
+ OpenGLContext::ReleaseFramebuffer( pFramebuffer );
+ }
+
+ mnWidth = nNewWidth;
+ mnHeight = nNewHeight;
+
+ CHECK_GL_ERROR();
+ return true;
+}
+
+/*
+ "Area" scaling algorithm, which seems to give better results for downscaling
+ than other algorithms. The principle (taken from opencv, see resize.cl)
+ is that each resulting pixel is the average of all the source pixel values
+ it represents. Which is trivial in the case of exact multiples for downscaling,
+ the generic case needs to also consider that some source pixels contribute
+ only partially to their resulting pixels (because of non-integer multiples).
+*/
+bool OpenGLSalBitmap::ImplScaleArea( const rtl::Reference< OpenGLContext > &xContext,
+ double rScaleX, double rScaleY )
+{
+ int nNewWidth( mnWidth * rScaleX );
+ int nNewHeight( mnHeight * rScaleY );
+
+ if( nNewWidth == mnWidth && nNewHeight == mnHeight )
+ return true;
+
+ double ixscale = 1 / rScaleX;
+ double iyscale = 1 / rScaleY;
+ bool fast = ( ixscale == std::trunc( ixscale ) && iyscale == std::trunc( iyscale )
+ && int( nNewWidth * ixscale ) == mnWidth && int( nNewHeight * iyscale ) == mnHeight );
+
+ bool bTwoPasses = false;
+
+ // The generic case has arrays only up to 100 ratio downscaling, which is hopefully enough
+ // in practice, but protect against buffer overflows in case such an extreme case happens
+ // (and in such case the precision of the generic algorithm probably doesn't matter anyway).
+ if( ixscale > 100 || iyscale > 100 )
+ {
+ fast = true;
+ }
+ else
+ {
+ if (ixscale > 16 || iyscale > 16)
+ {
+ ixscale = std::floor(std::sqrt(ixscale));
+ iyscale = std::floor(std::sqrt(iyscale));
+ nNewWidth = int(mnWidth / ixscale);
+ rScaleX *= ixscale; // second pass x-scale factor
+ nNewHeight = int(mnHeight / iyscale);
+ rScaleY *= iyscale; // second pass y-scale factor
+ bTwoPasses = true;
+ }
+ }
+
+ // TODO Make sure the framebuffer is alright
+
+ OString sUseReducedRegisterVariantDefine;
+ if (xContext->getOpenGLCapabilitySwitch().mbLimitedShaderRegisters)
+ sUseReducedRegisterVariantDefine = OString("#define USE_REDUCED_REGISTER_VARIANT\n");
+
+ OpenGLProgram* pProgram = xContext->UseProgram( "textureVertexShader",
+ fast ? OUString( "areaScaleFastFragmentShader" ) : OUString( "areaScaleFragmentShader" ),
+ sUseReducedRegisterVariantDefine);
+
+ if( pProgram == nullptr )
+ return false;
+
+ OpenGLTexture aScratchTex(nNewWidth, nNewHeight);
+
+ OpenGLFramebuffer* pFramebuffer = xContext->AcquireFramebuffer( aScratchTex );
+
+ // NOTE: This setup is also done in OpenGLSalGraphicsImpl::DrawTransformedTexture().
+ if( fast )
+ {
+ pProgram->SetUniform1i( "xscale", ixscale );
+ pProgram->SetUniform1i( "yscale", iyscale );
+ // The shader operates on pixels in the surrounding area, so it's necessary
+ // to know the step in texture coordinates to get to the next pixel.
+ // With a texture atlas the "texture" is just a subtexture of a larger texture,
+ // so while with a normal texture we'd map between <0.0,1.0> and <0,mnWidth>,
+ // with a subtexture the texture coordinates range is smaller.
+ GLfloat srcCoords[ 8 ];
+ maTexture.GetWholeCoord( srcCoords );
+ pProgram->SetUniform1f( "xstep", ( srcCoords[ 4 ] - srcCoords[ 0 ] ) / mnWidth );
+ pProgram->SetUniform1f( "ystep", ( srcCoords[ 5 ] - srcCoords[ 1 ] ) / mnHeight );
+ pProgram->SetUniform1f( "ratio", 1.0 / ( ixscale * iyscale ));
+ }
+ else
+ {
+ pProgram->SetUniform1f( "xscale", ixscale );
+ pProgram->SetUniform1f( "yscale", iyscale );
+ pProgram->SetUniform1i( "swidth", mnWidth );
+ pProgram->SetUniform1i( "sheight", mnHeight );
+ // The shader internally actually operates on pixel coordinates,
+ // so it needs to know how to convert to those from the texture coordinates.
+ // With a simple texture that would mean converting e.g. between
+ // <0,mnWidth-1> and <0.0,1.0> coordinates.
+ // However with a texture atlas the "texture" is just a subtexture
+ // of a larger texture, so the texture coordinates need offset and ratio
+ // conversion too.
+ GLfloat srcCoords[ 8 ];
+ maTexture.GetWholeCoord( srcCoords );
+ pProgram->SetUniform1f( "xoffset", srcCoords[ 0 ] );
+ pProgram->SetUniform1f( "yoffset", srcCoords[ 1 ] );
+ pProgram->SetUniform1f( "xtopixelratio", nNewWidth / ( srcCoords[ 4 ] - srcCoords[ 0 ] ));
+ pProgram->SetUniform1f( "ytopixelratio", nNewHeight / ( srcCoords[ 5 ] - srcCoords[ 1 ] ));
+ pProgram->SetUniform1f( "xfrompixelratio", ( srcCoords[ 4 ] - srcCoords[ 0 ] ) / mnWidth );
+ pProgram->SetUniform1f( "yfrompixelratio", ( srcCoords[ 5 ] - srcCoords[ 1 ] ) / mnHeight );
+ }
+
+ pProgram->SetTexture( "sampler", maTexture );
+ pProgram->DrawTexture( maTexture );
+ pProgram->Clean();
+
+ OpenGLContext::ReleaseFramebuffer(pFramebuffer);
+
+ CHECK_GL_ERROR();
+
+ if (bTwoPasses)
+ {
+ mnWidth = nNewWidth;
+ mnHeight = nNewHeight;
+
+ nNewWidth = round(mnWidth * rScaleX);
+ nNewHeight = round(mnHeight * rScaleY);
+
+ ixscale = 1 / rScaleX;
+ iyscale = 1 / rScaleY;
+
+ pProgram = xContext->UseProgram("textureVertexShader", "areaScaleFragmentShader", sUseReducedRegisterVariantDefine);
+ if (pProgram == nullptr)
+ return false;
+
+ OpenGLTexture aScratchTex2(nNewWidth, nNewHeight);
+
+ pFramebuffer = xContext->AcquireFramebuffer(aScratchTex2);
+
+ pProgram->SetUniform1f("xscale", ixscale);
+ pProgram->SetUniform1f("yscale", iyscale);
+ pProgram->SetUniform1i("swidth", mnWidth);
+ pProgram->SetUniform1i("sheight", mnHeight);
+
+ GLfloat srcCoords[ 8 ];
+ aScratchTex.GetWholeCoord( srcCoords );
+ pProgram->SetUniform1f( "xoffset", srcCoords[ 0 ] );
+ pProgram->SetUniform1f( "yoffset", srcCoords[ 1 ] );
+ pProgram->SetUniform1f( "xtopixelratio", nNewWidth / ( srcCoords[ 4 ] - srcCoords[ 0 ] ));
+ pProgram->SetUniform1f( "ytopixelratio", nNewHeight / ( srcCoords[ 5 ] - srcCoords[ 1 ] ));
+ pProgram->SetUniform1f( "xfrompixelratio", ( srcCoords[ 4 ] - srcCoords[ 0 ] ) / mnWidth );
+ pProgram->SetUniform1f( "yfrompixelratio", ( srcCoords[ 5 ] - srcCoords[ 1 ] ) / mnHeight );
+
+ pProgram->SetTexture("sampler", aScratchTex);
+ pProgram->DrawTexture(aScratchTex);
+ pProgram->Clean();
+
+ OpenGLContext::ReleaseFramebuffer(pFramebuffer);
+
+ CHECK_GL_ERROR();
+
+ maTexture = aScratchTex2;
+ mnWidth = nNewWidth;
+ mnHeight = nNewHeight;
+ }
+ else
+ {
+ maTexture = aScratchTex;
+ mnWidth = nNewWidth;
+ mnHeight = nNewHeight;
+ }
+
+ return true;
+}
+
+void OpenGLSalBitmap::ImplScale( const double& rScaleX, const double& rScaleY, BmpScaleFlag nScaleFlag )
+{
+ VCL_GL_INFO( "::ImplScale" );
+
+ mpUserBuffer.reset();
+ OpenGLVCLContextZone aContextZone;
+ rtl::Reference<OpenGLContext> xContext = OpenGLContext::getVCLContext();
+ xContext->state().scissor().disable();
+ xContext->state().stencil().disable();
+
+ if (rScaleX <= 1 && rScaleY <= 1)
+ {
+ nScaleFlag = BmpScaleFlag::BestQuality;
+ }
+
+ if( nScaleFlag == BmpScaleFlag::Fast )
+ {
+ ImplScaleFilter( xContext, rScaleX, rScaleY, GL_NEAREST );
+ }
+ else if( nScaleFlag == BmpScaleFlag::BiLinear )
+ {
+ ImplScaleFilter( xContext, rScaleX, rScaleY, GL_LINEAR );
+ }
+ else if( nScaleFlag == BmpScaleFlag::Default )
+ {
+ const Lanczos3Kernel aKernel;
+
+ ImplScaleConvolution( xContext, rScaleX, rScaleY, aKernel );
+ }
+ else if( nScaleFlag == BmpScaleFlag::BestQuality && rScaleX <= 1 && rScaleY <= 1 )
+ { // Use area scaling for best quality, but only if downscaling.
+ ImplScaleArea( xContext, rScaleX, rScaleY );
+ }
+ else if( nScaleFlag == BmpScaleFlag::Lanczos || nScaleFlag == BmpScaleFlag::BestQuality )
+ {
+ const Lanczos3Kernel aKernel;
+
+ ImplScaleConvolution( xContext, rScaleX, rScaleY, aKernel );
+ }
+ else
+ SAL_WARN( "vcl.opengl", "Invalid flag for scaling operation" );
+}
+
+bool OpenGLSalBitmap::ScalingSupported() const
+{
+ return true;
+}
+
+bool OpenGLSalBitmap::Scale( const double& rScaleX, const double& rScaleY, BmpScaleFlag nScaleFlag )
+{
+ OpenGLVCLContextZone aContextZone;
+
+ VCL_GL_INFO("::Scale " << int(nScaleFlag)
+ << " from " << mnWidth << "x" << mnHeight
+ << " to " << (mnWidth * rScaleX) << "x" << (mnHeight * rScaleY) );
+
+ if( nScaleFlag == BmpScaleFlag::Fast ||
+ nScaleFlag == BmpScaleFlag::BiLinear ||
+ nScaleFlag == BmpScaleFlag::Lanczos ||
+ nScaleFlag == BmpScaleFlag::Default ||
+ nScaleFlag == BmpScaleFlag::BestQuality )
+ {
+ ImplScale( rScaleX, rScaleY, nScaleFlag );
+ return true;
+ }
+
+ return false;
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */