/* SPDX-License-Identifier: LGPL-2.1-or-later */ /* * Copyright (C) 2020, Linaro * * viewfinderGL.cpp - OpenGL Viewfinder for rendering by OpenGL shader */ #include "viewfinder_gl.h" #include <array> #include <QByteArray> #include <QFile> #include <QImage> #include <QStringList> #include <libcamera/formats.h> #include "../cam/image.h" static const QList<libcamera::PixelFormat> supportedFormats{ /* YUV - packed (single plane) */ libcamera::formats::UYVY, libcamera::formats::VYUY, libcamera::formats::YUYV, libcamera::formats::YVYU, /* YUV - semi planar (two planes) */ libcamera::formats::NV12, libcamera::formats::NV21, libcamera::formats::NV16, libcamera::formats::NV61, libcamera::formats::NV24, libcamera::formats::NV42, /* YUV - fully planar (three planes) */ libcamera::formats::YUV420, libcamera::formats::YVU420, /* RGB */ libcamera::formats::ABGR8888, libcamera::formats::ARGB8888, libcamera::formats::BGRA8888, libcamera::formats::RGBA8888, libcamera::formats::BGR888, libcamera::formats::RGB888, /* Raw Bayer 8-bit */ libcamera::formats::SBGGR8, libcamera::formats::SGBRG8, libcamera::formats::SGRBG8, libcamera::formats::SRGGB8, /* Raw Bayer 10-bit packed */ libcamera::formats::SBGGR10_CSI2P, libcamera::formats::SGBRG10_CSI2P, libcamera::formats::SGRBG10_CSI2P, libcamera::formats::SRGGB10_CSI2P, /* Raw Bayer 12-bit packed */ libcamera::formats::SBGGR12_CSI2P, libcamera::formats::SGBRG12_CSI2P, libcamera::formats::SGRBG12_CSI2P, libcamera::formats::SRGGB12_CSI2P, }; ViewFinderGL::ViewFinderGL(QWidget *parent) : QOpenGLWidget(parent), buffer_(nullptr), colorSpace_(libcamera::ColorSpace::Raw), image_(nullptr), vertexBuffer_(QOpenGLBuffer::VertexBuffer) { } ViewFinderGL::~ViewFinderGL() { removeShader(); } const QList<libcamera::PixelFormat> &ViewFinderGL::nativeFormats() const { return supportedFormats; } int ViewFinderGL::setFormat(const libcamera::PixelFormat &format, const QSize &size, const libcamera::ColorSpace &colorSpace, unsigned int stride) { if (format != format_ || colorSpace != colorSpace_) { /* * If the fragment already exists, remove it and create a new * one for the new format. */ if (shaderProgram_.isLinked()) { shaderProgram_.release(); shaderProgram_.removeShader(fragmentShader_.get()); fragmentShader_.reset(); } if (!selectFormat(format)) return -1; selectColorSpace(colorSpace); format_ = format; colorSpace_ = colorSpace; } size_ = size; stride_ = stride; updateGeometry(); return 0; } void ViewFinderGL::stop() { if (buffer_) { renderComplete(buffer_); buffer_ = nullptr; image_ = nullptr; } } QImage ViewFinderGL::getCurrentImage() { QMutexLocker locker(&mutex_); return grabFramebuffer(); } void ViewFinderGL::render(libcamera::FrameBuffer *buffer, Image *image) { if (buffer_) renderComplete(buffer_); image_ = image; update(); buffer_ = buffer; } bool ViewFinderGL::selectFormat(const libcamera::PixelFormat &format) { bool ret = true; /* Set min/mag filters to GL_LINEAR by default. */ textureMinMagFilters_ = GL_LINEAR; /* Use identity.vert as the default vertex shader. */ vertexShaderFile_ = ":identity.vert"; fragmentShaderDefines_.clear(); switch (format) { case libcamera::formats::NV12: horzSubSample_ = 2; vertSubSample_ = 2; fragmentShaderDefines_.append("#define YUV_PATTERN_UV"); fragmentShaderFile_ = ":YUV_2_planes.frag"; break; case libcamera::formats::NV21: horzSubSample_ = 2; vertSubSample_ = 2; fragmentShaderDefines_.append("#define YUV_PATTERN_VU"); fragmentShaderFile_ = ":YUV_2_planes.frag"; break; case libcamera::formats::NV16: horzSubSample_ = 2; vertSubSample_ = 1; fragmentShaderDefines_.append("#define YUV_PATTERN_UV"); fragmentShaderFile_ = ":YUV_2_planes.frag"; break; case libcamera::formats::NV61: horzSubSample_ = 2; vertSubSample_ = 1; fragmentShaderDefines_.append("#define YUV_PATTERN_VU"); fragmentShaderFile_ = ":YUV_2_planes.frag"; break; case libcamera::formats::NV24: horzSubSample_ = 1; vertSubSample_ = 1; fragmentShaderDefines_.append("#define YUV_PATTERN_UV"); fragmentShaderFile_ = ":YUV_2_planes.frag"; break; case libcamera::formats::NV42: horzSubSample_ = 1; vertSubSample_ = 1; fragmentShaderDefines_.append("#define YUV_PATTERN_VU"); fragmentShaderFile_ = ":YUV_2_planes.frag"; break; case libcamera::formats::YUV420: horzSubSample_ = 2; vertSubSample_ = 2; fragmentShaderFile_ = ":YUV_3_planes.frag"; break; case libcamera::formats::YVU420: horzSubSample_ = 2; vertSubSample_ = 2; fragmentShaderFile_ = ":YUV_3_planes.frag"; break; case libcamera::formats::UYVY: fragmentShaderDefines_.append("#define YUV_PATTERN_UYVY"); fragmentShaderFile_ = ":YUV_packed.frag"; break; case libcamera::formats::VYUY: fragmentShaderDefines_.append("#define YUV_PATTERN_VYUY"); fragmentShaderFile_ = ":YUV_packed.frag"; break; case libcamera::formats::YUYV: fragmentShaderDefines_.append("#define YUV_PATTERN_YUYV"); fragmentShaderFile_ = ":YUV_packed.frag"; break; case libcamera::formats::YVYU: fragmentShaderDefines_.append("#define YUV_PATTERN_YVYU"); fragmentShaderFile_ = ":YUV_packed.frag"; break; case libcamera::formats::ABGR8888: fragmentShaderDefines_.append("#define RGB_PATTERN rgb"); fragmentShaderFile_ = ":RGB.frag"; break; case libcamera::formats::ARGB8888: fragmentShaderDefines_.append("#define RGB_PATTERN bgr"); fragmentShaderFile_ = ":RGB.frag"; break; case libcamera::formats::BGRA8888: fragmentShaderDefines_.append("#define RGB_PATTERN gba"); fragmentShaderFile_ = ":RGB.frag"; break; case libcamera::formats::RGBA8888: fragmentShaderDefines_.append("#define RGB_PATTERN abg"); fragmentShaderFile_ = ":RGB.frag"; break; case libcamera::formats::BGR888: fragmentShaderDefines_.append("#define RGB_PATTERN rgb"); fragmentShaderFile_ = ":RGB.frag"; break; case libcamera::formats::RGB888: fragmentShaderDefines_.append("#define RGB_PATTERN bgr"); fragmentShaderFile_ = ":RGB.frag"; break; case libcamera::formats::SBGGR8: firstRed_.setX(1.0); firstRed_.setY(1.0); vertexShaderFile_ = ":bayer_8.vert"; fragmentShaderFile_ = ":bayer_8.frag"; textureMinMagFilters_ = GL_NEAREST; break; case libcamera::formats::SGBRG8: firstRed_.setX(0.0); firstRed_.setY(1.0); vertexShaderFile_ = ":bayer_8.vert"; fragmentShaderFile_ = ":bayer_8.frag"; textureMinMagFilters_ = GL_NEAREST; break; case libcamera::formats::SGRBG8: firstRed_.setX(1.0); firstRed_.setY(0.0); vertexShaderFile_ = ":bayer_8.vert"; fragmentShaderFile_ = ":bayer_8.frag"; textureMinMagFilters_ = GL_NEAREST; break; case libcamera::formats::SRGGB8: firstRed_.setX(0.0); firstRed_.setY(0.0); vertexShaderFile_ = ":bayer_8.vert"; fragmentShaderFile_ = ":bayer_8.frag"; textureMinMagFilters_ = GL_NEAREST; break; case libcamera::formats::SBGGR10_CSI2P: firstRed_.setX(1.0); firstRed_.setY(1.0); fragmentShaderDefines_.append("#define RAW10P"); fragmentShaderFile_ = ":bayer_1x_packed.frag"; textureMinMagFilters_ = GL_NEAREST; break; case libcamera::formats::SGBRG10_CSI2P: firstRed_.setX(0.0); firstRed_.setY(1.0); fragmentShaderDefines_.append("#define RAW10P"); fragmentShaderFile_ = ":bayer_1x_packed.frag"; textureMinMagFilters_ = GL_NEAREST; break; case libcamera::formats::SGRBG10_CSI2P: firstRed_.setX(1.0); firstRed_.setY(0.0); fragmentShaderDefines_.append("#define RAW10P"); fragmentShaderFile_ = ":bayer_1x_packed.frag"; textureMinMagFilters_ = GL_NEAREST; break; case libcamera::formats::SRGGB10_CSI2P: firstRed_.setX(0.0); firstRed_.setY(0.0); fragmentShaderDefines_.append("#define RAW10P"); fragmentShaderFile_ = ":bayer_1x_packed.frag"; textureMinMagFilters_ = GL_NEAREST; break; case libcamera::formats::SBGGR12_CSI2P: firstRed_.setX(1.0); firstRed_.setY(1.0); fragmentShaderDefines_.append("#define RAW12P"); fragmentShaderFile_ = ":bayer_1x_packed.frag"; textureMinMagFilters_ = GL_NEAREST; break; case libcamera::formats::SGBRG12_CSI2P: firstRed_.setX(0.0); firstRed_.setY(1.0); fragmentShaderDefines_.append("#define RAW12P"); fragmentShaderFile_ = ":bayer_1x_packed.frag"; textureMinMagFilters_ = GL_NEAREST; break; case libcamera::formats::SGRBG12_CSI2P: firstRed_.setX(1.0); firstRed_.setY(0.0); fragmentShaderDefines_.append("#define RAW12P"); fragmentShaderFile_ = ":bayer_1x_packed.frag"; textureMinMagFilters_ = GL_NEAREST; break; case libcamera::formats::SRGGB12_CSI2P: firstRed_.setX(0.0); firstRed_.setY(0.0); fragmentShaderDefines_.append("#define RAW12P"); fragmentShaderFile_ = ":bayer_1x_packed.frag"; textureMinMagFilters_ = GL_NEAREST; break; default: ret = false; qWarning() << "[ViewFinderGL]:" << "format not supported."; break; }; return ret; } void ViewFinderGL::selectColorSpace(const libcamera::ColorSpace &colorSpace) { std::array<double, 9> yuv2rgb; /* OpenGL stores arrays in column-major order. */ switch (colorSpace.ycbcrEncoding) { case libcamera::ColorSpace::YcbcrEncoding::None: default: yuv2rgb = { 1.0000, 0.0000, 0.0000, 0.0000, 1.0000, 0.0000, 0.0000, 0.0000, 1.0000, }; break; case libcamera::ColorSpace::YcbcrEncoding::Rec601: yuv2rgb = { 1.0000, 1.0000, 1.0000, 0.0000, -0.3441, 1.7720, 1.4020, -0.7141, 0.0000, }; break; case libcamera::ColorSpace::YcbcrEncoding::Rec709: yuv2rgb = { 1.0000, 1.0000, 1.0000, 0.0000, -0.1873, 1.8856, 1.5748, -0.4681, 0.0000, }; break; case libcamera::ColorSpace::YcbcrEncoding::Rec2020: yuv2rgb = { 1.0000, 1.0000, 1.0000, 0.0000, -0.1646, 1.8814, 1.4746, -0.5714, 0.0000, }; break; } double offset; switch (colorSpace.range) { case libcamera::ColorSpace::Range::Full: default: offset = 0.0; break; case libcamera::ColorSpace::Range::Limited: offset = 16.0; for (unsigned int i = 0; i < 3; ++i) yuv2rgb[i] *= 255.0 / 219.0; for (unsigned int i = 4; i < 9; ++i) yuv2rgb[i] *= 255.0 / 224.0; break; } QStringList matrix; for (double coeff : yuv2rgb) matrix.append(QString::number(coeff, 'f')); fragmentShaderDefines_.append("#define YUV2RGB_MATRIX " + matrix.join(", ")); fragmentShaderDefines_.append(QString("#define YUV2RGB_Y_OFFSET %1") .arg(offset, 0, 'f', 1)); } bool ViewFinderGL::createVertexShader() { /* Create Vertex Shader */ vertexShader_ = std::make_unique<QOpenGLShader>(QOpenGLShader::Vertex, this); /* Compile the vertex shader */ if (!vertexShader_->compileSourceFile(vertexShaderFile_)) { qWarning() << "[ViewFinderGL]:" << vertexShader_->log(); return false; } shaderProgram_.addShader(vertexShader_.get()); return true; } bool ViewFinderGL::createFragmentShader() { int attributeVertex; int attributeTexture; /* * Create the fragment shader, compile it, and add it to the shader * program. The #define macros stored in fragmentShaderDefines_, if * any, are prepended to the source code. */ fragmentShader_ = std::make_unique<QOpenGLShader>(QOpenGLShader::Fragment, this); QFile file(fragmentShaderFile_); if (!file.open(QIODevice::ReadOnly | QIODevice::Text)) { qWarning() << "Shader" << fragmentShaderFile_ << "not found"; return false; } QString defines = fragmentShaderDefines_.join('\n') + "\n"; QByteArray src = file.readAll(); src.prepend(defines.toUtf8()); if (!fragmentShader_->compileSourceCode(src)) { qWarning() << "[ViewFinderGL]:" << fragmentShader_->log(); return false; } shaderProgram_.addShader(fragmentShader_.get()); /* Link shader pipeline */ if (!shaderProgram_.link()) { qWarning() << "[ViewFinderGL]:" << shaderProgram_.log(); close(); } /* Bind shader pipeline for use */ if (!shaderProgram_.bind()) { qWarning() << "[ViewFinderGL]:" << shaderProgram_.log(); close(); } attributeVertex = shaderProgram_.attributeLocation("vertexIn"); attributeTexture = shaderProgram_.attributeLocation("textureIn"); shaderProgram_.enableAttributeArray(attributeVertex); shaderProgram_.setAttributeBuffer(attributeVertex, GL_FLOAT, 0, 2, 2 * sizeof(GLfloat)); shaderProgram_.enableAttributeArray(attributeTexture); shaderProgram_.setAttributeBuffer(attributeTexture, GL_FLOAT, 8 * sizeof(GLfloat), 2, 2 * sizeof(GLfloat)); textureUniformY_ = shaderProgram_.uniformLocation("tex_y"); textureUniformU_ = shaderProgram_.uniformLocation("tex_u"); textureUniformV_ = shaderProgram_.uniformLocation("tex_v"); textureUniformStep_ = shaderProgram_.uniformLocation("tex_step"); textureUniformSize_ = shaderProgram_.uniformLocation("tex_size"); textureUniformStrideFactor_ = shaderProgram_.uniformLocation("stride_factor"); textureUniformBayerFirstRed_ = shaderProgram_.uniformLocation("tex_bayer_first_red"); /* Create the textures. */ for (std::unique_ptr<QOpenGLTexture> &texture : textures_) { if (texture) continue; texture = std::make_unique<QOpenGLTexture>(QOpenGLTexture::Target2D); texture->create(); } return true; } void ViewFinderGL::configureTexture(QOpenGLTexture &texture) { glBindTexture(GL_TEXTURE_2D, texture.textureId()); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, textureMinMagFilters_); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, textureMinMagFilters_); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); } void ViewFinderGL::removeShader() { if (shaderProgram_.isLinked()) { shaderProgram_.release(); shaderProgram_.removeAllShaders(); } } void ViewFinderGL::initializeGL() { initializeOpenGLFunctions(); glEnable(GL_TEXTURE_2D); glDisable(GL_DEPTH_TEST); static const GLfloat coordinates[2][4][2]{ { /* Vertex coordinates */ { -1.0f, -1.0f }, { -1.0f, +1.0f }, { +1.0f, +1.0f }, { +1.0f, -1.0f }, }, { /* Texture coordinates */ { 0.0f, 1.0f }, { 0.0f, 0.0f }, { 1.0f, 0.0f }, { 1.0f, 1.0f }, }, }; vertexBuffer_.create(); vertexBuffer_.bind(); vertexBuffer_.allocate(coordinates, sizeof(coordinates)); /* Create Vertex Shader */ if (!createVertexShader()) qWarning() << "[ViewFinderGL]: create vertex shader failed."; glClearColor(1.0f, 1.0f, 1.0f, 0.0f); } void ViewFinderGL::doRender() { /* Stride of the first plane, in pixels. */ unsigned int stridePixels; switch (format_) { case libcamera::formats::NV12: case libcamera::formats::NV21: case libcamera::formats::NV16: case libcamera::formats::NV61: case libcamera::formats::NV24: case libcamera::formats::NV42: /* Activate texture Y */ glActiveTexture(GL_TEXTURE0); configureTexture(*textures_[0]); glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, stride_, size_.height(), 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, image_->data(0).data()); shaderProgram_.setUniformValue(textureUniformY_, 0); /* Activate texture UV/VU */ glActiveTexture(GL_TEXTURE1); configureTexture(*textures_[1]); glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE_ALPHA, stride_ / horzSubSample_, size_.height() / vertSubSample_, 0, GL_LUMINANCE_ALPHA, GL_UNSIGNED_BYTE, image_->data(1).data()); shaderProgram_.setUniformValue(textureUniformU_, 1); stridePixels = stride_; break; case libcamera::formats::YUV420: /* Activate texture Y */ glActiveTexture(GL_TEXTURE0); configureTexture(*textures_[0]); glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, stride_, size_.height(), 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, image_->data(0).data()); shaderProgram_.setUniformValue(textureUniformY_, 0); /* Activate texture U */ glActiveTexture(GL_TEXTURE1); configureTexture(*textures_[1]); glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, stride_ / horzSubSample_, size_.height() / vertSubSample_, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, image_->data(1).data()); shaderProgram_.setUniformValue(textureUniformU_, 1); /* Activate texture V */ glActiveTexture(GL_TEXTURE2); configureTexture(*textures_[2]); glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, stride_ / horzSubSample_, size_.height() / vertSubSample_, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, image_->data(2).data()); shaderProgram_.setUniformValue(textureUniformV_, 2); stridePixels = stride_; break; case libcamera::formats::YVU420: /* Activate texture Y */ glActiveTexture(GL_TEXTURE0); configureTexture(*textures_[0]); glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, stride_, size_.height(), 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, image_->data(0).data()); shaderProgram_.setUniformValue(textureUniformY_, 0); /* Activate texture V */ glActiveTexture(GL_TEXTURE2); configureTexture(*textures_[2]); glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, stride_ / horzSubSample_, size_.height() / vertSubSample_, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, image_->data(1).data()); shaderProgram_.setUniformValue(textureUniformV_, 2); /* Activate texture U */ glActiveTexture(GL_TEXTURE1); configureTexture(*textures_[1]); glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, stride_ / horzSubSample_, size_.height() / vertSubSample_, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, image_->data(2).data()); shaderProgram_.setUniformValue(textureUniformU_, 1); stridePixels = stride_; break; case libcamera::formats::UYVY: case libcamera::formats::VYUY: case libcamera::formats::YUYV: case libcamera::formats::YVYU: /* * Packed YUV formats are stored in a RGBA texture to match the * OpenGL texel size with the 4 bytes repeating pattern in YUV. * The texture width is thus half of the image_ with. */ glActiveTexture(GL_TEXTURE0); configureTexture(*textures_[0]); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, stride_ / 4, size_.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE, image_->data(0).data()); shaderProgram_.setUniformValue(textureUniformY_, 0); /* * The shader needs the step between two texture pixels in the * horizontal direction, expressed in texture coordinate units * ([0, 1]). There are exactly width - 1 steps between the * leftmost and rightmost texels. */ shaderProgram_.setUniformValue(textureUniformStep_, 1.0f / (size_.width() / 2 - 1), 1.0f /* not used */); stridePixels = stride_ / 2; break; case libcamera::formats::ABGR8888: case libcamera::formats::ARGB8888: case libcamera::formats::BGRA8888: case libcamera::formats::RGBA8888: glActiveTexture(GL_TEXTURE0); configureTexture(*textures_[0]); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, stride_ / 4, size_.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE, image_->data(0).data()); shaderProgram_.setUniformValue(textureUniformY_, 0); stridePixels = stride_ / 4; break; case libcamera::formats::BGR888: case libcamera::formats::RGB888: glActiveTexture(GL_TEXTURE0); configureTexture(*textures_[0]); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, stride_ / 3, size_.height(), 0, GL_RGB, GL_UNSIGNED_BYTE, image_->data(0).data()); shaderProgram_.setUniformValue(textureUniformY_, 0); stridePixels = stride_ / 3; break; case libcamera::formats::SBGGR8: case libcamera::formats::SGBRG8: case libcamera::formats::SGRBG8: case libcamera::formats::SRGGB8: case libcamera::formats::SBGGR10_CSI2P: case libcamera::formats::SGBRG10_CSI2P: case libcamera::formats::SGRBG10_CSI2P: case libcamera::formats::SRGGB10_CSI2P: case libcamera::formats::SBGGR12_CSI2P: case libcamera::formats::SGBRG12_CSI2P: case libcamera::formats::SGRBG12_CSI2P: case libcamera::formats::SRGGB12_CSI2P: /* * Raw Bayer 8-bit, and packed raw Bayer 10-bit/12-bit formats * are stored in a GL_LUMINANCE texture. The texture width is * equal to the stride. */ glActiveTexture(GL_TEXTURE0); configureTexture(*textures_[0]); glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, stride_, size_.height(), 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, image_->data(0).data()); shaderProgram_.setUniformValue(textureUniformY_, 0); shaderProgram_.setUniformValue(textureUniformBayerFirstRed_, firstRed_); shaderProgram_.setUniformValue(textureUniformSize_, size_.width(), /* in pixels */ size_.height()); shaderProgram_.setUniformValue(textureUniformStep_, 1.0f / (stride_ - 1), 1.0f / (size_.height() - 1)); /* * The stride is already taken into account in the shaders, set * the generic stride factor to 1.0. */ stridePixels = size_.width(); break; default: stridePixels = size_.width(); break; }; /* * Compute the stride factor for the vertex shader, to map the * horizontal texture coordinate range [0.0, 1.0] to the active portion * of the image. */ shaderProgram_.setUniformValue(textureUniformStrideFactor_, static_cast<float>(size_.width() - 1) / (stridePixels - 1)); } void ViewFinderGL::paintGL() { if (!fragmentShader_) if (!createFragmentShader()) { qWarning() << "[ViewFinderGL]:" << "create fragment shader failed."; } if (image_) { glClearColor(0.0, 0.0, 0.0, 1.0); glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); doRender(); glDrawArrays(GL_TRIANGLE_FAN, 0, 4); } } void ViewFinderGL::resizeGL(int w, int h) { glViewport(0, 0, w, h); } QSize ViewFinderGL::sizeHint() const { return size_.isValid() ? size_ : QSize(640, 480); }