diff options
Diffstat (limited to 'src/plugins/platforms/eglconvenience/qeglconvenience.cpp')
-rw-r--r-- | src/plugins/platforms/eglconvenience/qeglconvenience.cpp | 316 |
1 files changed, 316 insertions, 0 deletions
diff --git a/src/plugins/platforms/eglconvenience/qeglconvenience.cpp b/src/plugins/platforms/eglconvenience/qeglconvenience.cpp new file mode 100644 index 0000000..b203fe8 --- /dev/null +++ b/src/plugins/platforms/eglconvenience/qeglconvenience.cpp @@ -0,0 +1,316 @@ +/**************************************************************************** +** +** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies). +** All rights reserved. +** Contact: Nokia Corporation (qt-info@nokia.com) +** +** This file is part of the plugins of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the Technology Preview License Agreement accompanying +** this package. +** +** GNU Lesser General Public License Usage +** Alternatively, this file may be used under the terms of the GNU Lesser +** General Public License version 2.1 as published by the Free Software +** Foundation and appearing in the file LICENSE.LGPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU Lesser General Public License version 2.1 requirements +** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain additional +** rights. These rights are described in the Nokia Qt LGPL Exception +** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. +** +** If you have questions regarding the use of this file, please contact +** Nokia at qt-info@nokia.com. +** +** +** +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "qeglconvenience.h" + +QT_BEGIN_NAMESPACE + +QVector<EGLint> q_createConfigAttributesFromFormat(const QPlatformWindowFormat &format) +{ + int redSize = format.redBufferSize(); + int greenSize = format.greenBufferSize(); + int blueSize = format.blueBufferSize(); + int alphaSize = format.alphaBufferSize(); + int depthSize = format.depthBufferSize(); + int stencilSize = format.stencilBufferSize(); + int sampleCount = format.samples(); + + // QPlatformWindowFormat uses a magic value of -1 to indicate "don't care", even when a buffer of that + // type has been requested. So we must check QPlatformWindowFormat's booleans too if size is -1: + if (format.alpha() && alphaSize <= 0) + alphaSize = 1; + if (format.depth() && depthSize <= 0) + depthSize = 1; + if (format.stencil() && stencilSize <= 0) + stencilSize = 1; + if (format.sampleBuffers() && sampleCount <= 0) + sampleCount = 1; + + // We want to make sure 16-bit configs are chosen over 32-bit configs as they will provide + // the best performance. The EGL config selection algorithm is a bit stange in this regard: + // The selection criteria for EGL_BUFFER_SIZE is "AtLeast", so we can't use it to discard + // 32-bit configs completely from the selection. So it then comes to the sorting algorithm. + // The red/green/blue sizes have a sort priority of 3, so they are sorted by first. The sort + // order is special and described as "by larger _total_ number of color bits.". So EGL will + // put 32-bit configs in the list before the 16-bit configs. However, the spec also goes on + // to say "If the requested number of bits in attrib_list for a particular component is 0, + // then the number of bits for that component is not considered". This part of the spec also + // seems to imply that setting the red/green/blue bits to zero means none of the components + // are considered and EGL disregards the entire sorting rule. It then looks to the next + // highest priority rule, which is EGL_BUFFER_SIZE. Despite the selection criteria being + // "AtLeast" for EGL_BUFFER_SIZE, it's sort order is "smaller" meaning 16-bit configs are + // put in the list before 32-bit configs. So, to make sure 16-bit is preffered over 32-bit, + // we must set the red/green/blue sizes to zero. This has an unfortunate consequence that + // if the application sets the red/green/blue size to 5/6/5 on the QPlatformWindowFormat, + // they will probably get a 32-bit config, even when there's an RGB565 config available. + + // Now normalize the values so -1 becomes 0 + redSize = redSize > 0 ? redSize : 0; + greenSize = greenSize > 0 ? greenSize : 0; + blueSize = blueSize > 0 ? blueSize : 0; + alphaSize = alphaSize > 0 ? alphaSize : 0; + depthSize = depthSize > 0 ? depthSize : 0; + stencilSize = stencilSize > 0 ? stencilSize : 0; + sampleCount = sampleCount > 0 ? sampleCount : 0; + + QVector<EGLint> configAttributes; + + configAttributes.append(EGL_RED_SIZE); + configAttributes.append(redSize); + + configAttributes.append(EGL_GREEN_SIZE); + configAttributes.append(greenSize); + + configAttributes.append(EGL_BLUE_SIZE); + configAttributes.append(blueSize); + + configAttributes.append(EGL_ALPHA_SIZE); + configAttributes.append(alphaSize); + + configAttributes.append(EGL_DEPTH_SIZE); + configAttributes.append(depthSize); + + configAttributes.append(EGL_STENCIL_SIZE); + configAttributes.append(stencilSize); + + configAttributes.append(EGL_SAMPLES); + configAttributes.append(sampleCount); + + configAttributes.append(EGL_SAMPLE_BUFFERS); + configAttributes.append(sampleCount? 1:0); + + return configAttributes; +} + +bool q_reduceConfigAttributes(QVector<EGLint> *configAttributes) +{ + int i = -1; + // Reduce the complexity of a configuration request to ask for less + // because the previous request did not result in success. Returns + // true if the complexity was reduced, or false if no further + // reductions in complexity are possible. + + i = configAttributes->indexOf(EGL_SWAP_BEHAVIOR); + if (i >= 0) { + configAttributes->remove(i,2); + } + +#ifdef EGL_VG_ALPHA_FORMAT_PRE_BIT + // For OpenVG, we sometimes try to create a surface using a pre-multiplied format. If we can't + // find a config which supports pre-multiplied formats, remove the flag on the surface type: + + i = configAttributes->indexOf(EGL_SURFACE_TYPE); + if (i >= 0) { + EGLint surfaceType = configAttributes->at(i +1); + if (surfaceType & EGL_VG_ALPHA_FORMAT_PRE_BIT) { + surfaceType ^= EGL_VG_ALPHA_FORMAT_PRE_BIT; + configAttributes->replace(i+1,surfaceType); + return true; + } + } +#endif + + // EGL chooses configs with the highest color depth over + // those with smaller (but faster) lower color depths. One + // way around this is to set EGL_BUFFER_SIZE to 16, which + // trumps the others. Of course, there may not be a 16-bit + // config available, so it's the first restraint we remove. + i = configAttributes->indexOf(EGL_BUFFER_SIZE); + if (i >= 0) { + if (configAttributes->at(i+1) == 16) { + configAttributes->remove(i,2); + return true; + } + } + + i = configAttributes->indexOf(EGL_SAMPLE_BUFFERS); + if (i >= 0) { + configAttributes->remove(i,2); + i = configAttributes->indexOf(EGL_SAMPLES); + if (i >= 0) { + configAttributes->remove(i,2); + } + return true; + } + + i = configAttributes->indexOf(EGL_ALPHA_SIZE); + if (i >= 0) { + configAttributes->remove(i,2); +#if defined(EGL_BIND_TO_TEXTURE_RGBA) && defined(EGL_BIND_TO_TEXTURE_RGB) + i = configAttributes->indexOf(EGL_BIND_TO_TEXTURE_RGBA); + if (i >= 0) { + configAttributes->replace(i,EGL_BIND_TO_TEXTURE_RGB); + configAttributes->replace(i+1,TRUE); + + } +#endif + return true; + } + + i = configAttributes->indexOf(EGL_STENCIL_SIZE); + if (i >= 0) { + configAttributes->remove(i,2); + return true; + } + i = configAttributes->indexOf(EGL_DEPTH_SIZE); + if (i >= 0) { + configAttributes->remove(i,2); + return true; + } +#ifdef EGL_BIND_TO_TEXTURE_RGB + i = configAttributes->indexOf(EGL_BIND_TO_TEXTURE_RGB); + if (i >= 0) { + configAttributes->remove(i,2); + return true; + } +#endif + + return false; +} + +EGLConfig q_configFromQPlatformWindowFormat(EGLDisplay display, const QPlatformWindowFormat &format) +{ + EGLConfig cfg = 0; + QVector<EGLint> configureAttributes = q_createConfigAttributesFromFormat(format); + configureAttributes.append(EGL_SURFACE_TYPE); //we only support eglconfigs for windows for now + configureAttributes.append(EGL_WINDOW_BIT); + + configureAttributes.append(EGL_RENDERABLE_TYPE); + if (format.windowApi() == QPlatformWindowFormat::OpenVG) { + configureAttributes.append(EGL_OPENVG_BIT); + } else { + configureAttributes.append(EGL_OPENGL_ES2_BIT); + } + configureAttributes.append(EGL_NONE); + + do { + // Get the number of matching configurations for this set of properties. + EGLint matching = 0; + if (!eglChooseConfig(display, configureAttributes.constData(), 0, 0, &matching) || !matching) + continue; + +// // If we want the best pixel format, then return the first +// // matching configuration. +// if (match == QEgl::BestPixelFormat) { +// eglChooseConfig(display, props.properties(), &cfg, 1, &matching); +// if (matching < 1) +// continue; +// return cfg; +// } + + // Fetch all of the matching configurations and find the + // first that matches the pixel format we wanted. + int i = configureAttributes.indexOf(EGL_RED_SIZE); + int confAttrRed = configureAttributes.at(i+1); + i = configureAttributes.indexOf(EGL_GREEN_SIZE); + int confAttrGreen = configureAttributes.at(i+1); + i = configureAttributes.indexOf(EGL_BLUE_SIZE); + int confAttrBlue = configureAttributes.at(i+1); + i = configureAttributes.indexOf(EGL_ALPHA_SIZE); + int confAttrAlpha = configureAttributes.at(i+1); + + EGLint size = matching; + EGLConfig *configs = new EGLConfig [size]; + eglChooseConfig(display, configureAttributes.constData(), configs, size, &matching); + for (EGLint index = 0; index < size; ++index) { + EGLint red, green, blue, alpha; + eglGetConfigAttrib(display, configs[index], EGL_RED_SIZE, &red); + eglGetConfigAttrib(display, configs[index], EGL_GREEN_SIZE, &green); + eglGetConfigAttrib(display, configs[index], EGL_BLUE_SIZE, &blue); + eglGetConfigAttrib(display, configs[index], EGL_ALPHA_SIZE, &alpha); + if (red == confAttrRed && + green == confAttrGreen && + blue == confAttrBlue && + (confAttrAlpha == 0 || + alpha == confAttrAlpha)) { + cfg = configs[index]; + delete [] configs; + return cfg; + } + } + delete [] configs; + } while (q_reduceConfigAttributes(&configureAttributes)); + qWarning("Cant find EGLConfig, returning null config"); + return 0; +} + +QPlatformWindowFormat qt_qPlatformWindowFormatFromConfig(EGLDisplay display, const EGLConfig config) +{ + QPlatformWindowFormat format; + EGLint redSize = 0; + EGLint greenSize = 0; + EGLint blueSize = 0; + EGLint alphaSize = 0; + EGLint depthSize = 0; + EGLint stencilSize = 0; + EGLint sampleCount = 0; + EGLint level = 0; + + eglGetConfigAttrib(display, config, EGL_RED_SIZE, &redSize); + eglGetConfigAttrib(display, config, EGL_GREEN_SIZE, &greenSize); + eglGetConfigAttrib(display, config, EGL_BLUE_SIZE, &blueSize); + eglGetConfigAttrib(display, config, EGL_ALPHA_SIZE, &alphaSize); + eglGetConfigAttrib(display, config, EGL_DEPTH_SIZE, &depthSize); + eglGetConfigAttrib(display, config, EGL_STENCIL_SIZE, &stencilSize); + eglGetConfigAttrib(display, config, EGL_SAMPLES, &sampleCount); + eglGetConfigAttrib(display, config, EGL_LEVEL, &level); + + format.setRedBufferSize(redSize); + format.setGreenBufferSize(greenSize); + format.setBlueBufferSize(blueSize); + format.setAlphaBufferSize(alphaSize); + format.setDepthBufferSize(depthSize); + format.setStencilBufferSize(stencilSize); + format.setSamples(sampleCount); + format.setDirectRendering(true); // All EGL contexts are direct-rendered + format.setRgba(true); // EGL doesn't support colour index rendering + format.setStereo(false); // EGL doesn't support stereo buffers + format.setAccumBufferSize(0); // EGL doesn't support accululation buffers + + // Clear the EGL error state because some of the above may + // have errored out because the attribute is not applicable + // to the surface type. Such errors don't matter. + eglGetError(); + + return format; +} + +QT_END_NAMESPACE |