/**************************************************************************** ** ** Copyright (C) 2019 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the QtQuick module of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:LGPL$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and The Qt Company. For licensing terms ** and conditions see https://www.qt.io/terms-conditions. For further ** information use the contact form at https://www.qt.io/contact-us. ** ** GNU Lesser General Public License Usage ** Alternatively, this file may be used under the terms of the GNU Lesser ** General Public License version 3 as published by the Free Software ** Foundation and appearing in the file LICENSE.LGPL3 included in the ** packaging of this file. Please review the following information to ** ensure the GNU Lesser General Public License version 3 requirements ** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. ** ** GNU General Public License Usage ** Alternatively, this file may be used under the terms of the GNU ** General Public License version 2.0 or (at your option) the GNU General ** Public license version 3 or any later version approved by the KDE Free ** Qt Foundation. The licenses are as published by the Free Software ** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 ** included in the packaging of this file. Please review the following ** information to ensure the GNU General Public License requirements will ** be met: https://www.gnu.org/licenses/gpl-2.0.html and ** https://www.gnu.org/licenses/gpl-3.0.html. ** ** $QT_END_LICENSE$ ** ****************************************************************************/ #include "qsgmaterial.h" #include "qsgrenderer_p.h" #include "qsgmaterialshader_p.h" #if QT_CONFIG(opengl) # include # include # include # include # include #endif QT_BEGIN_NAMESPACE #if QT_CONFIG(opengl) const char *QSGMaterialShaderPrivate::loadShaderSource(QOpenGLShader::ShaderType type) const { const QStringList files = m_sourceFiles[type]; QSGShaderSourceBuilder builder; for (const QString &file : files) builder.appendSourceFile(file); m_sources[type] = builder.source(); return m_sources[type].constData(); } #endif /*! \class QSGMaterialShader \brief The QSGMaterialShader class represents an OpenGL shader program in the renderer. \inmodule QtQuick \ingroup qtquick-scenegraph-materials The QSGMaterialShader API is relatively low-level. A more convenient API, which provides almost all the same features, is available through QSGSimpleMaterialShader. \warning This class is only functional when running with the legacy OpenGL renderer of the Qt Quick scenegraph. The QSGMaterial and QSGMaterialShader form a tight relationship. For one scene graph (including nested graphs), there is one unique QSGMaterialShader instance which encapsulates the QOpenGLShaderProgram the scene graph uses to render that material, such as a shader to flat coloring of geometry. Each QSGGeometryNode can have a unique QSGMaterial containing the how the shader should be configured when drawing that node, such as the actual color used to render the geometry. An instance of QSGMaterialShader is never created explicitly by the user, it will be created on demand by the scene graph through QSGMaterial::createShader(). The scene graph will make sure that there is only one instance of each shader implementation through a scene graph. The source code returned from vertexShader() is used to control what the material does with the vertiex data that comes in from the geometry. The source code returned from the fragmentShader() is used to control what how the material should fill each individual pixel in the geometry. The vertex and fragment source code is queried once during initialization, changing what is returned from these functions later will not have any effect. The activate() function is called by the scene graph when a shader is is starting to be used. The deactivate function is called by the scene graph when the shader is no longer going to be used. While active, the scene graph may make one or more calls to updateState() which will update the state of the shader for each individual geometry to render. The attributeNames() returns the name of the attributes used in the vertexShader(). These are used in the default implementation of activate() and deactivate() to decide whice vertex registers are enabled. The initialize() function is called during program creation to allow subclasses to prepare for use, such as resolve uniform names in the vertexShader() and fragmentShader(). A minimal example: \code class Shader : public QSGMaterialShader { public: const char *vertexShader() const { return "attribute highp vec4 vertex; \n" "uniform highp mat4 matrix; \n" "void main() { \n" " gl_Position = matrix * vertex; \n" "}"; } const char *fragmentShader() const { return "uniform lowp float opacity; \n" "void main() { \n" " gl_FragColor = vec4(1, 0, 0, 1) * opacity; \n" "}"; } char const *const *attributeNames() const { static char const *const names[] = { "vertex", 0 }; return names; } void initialize() { QSGMaterialShader::initialize(); m_id_matrix = program()->uniformLocation("matrix"); m_id_opacity = program()->uniformLocation("opacity"); } void updateState(const RenderState &state, QSGMaterial *newMaterial, QSGMaterial *oldMaterial) { Q_ASSERT(program()->isLinked()); if (state.isMatrixDirty()) program()->setUniformValue(m_id_matrix, state.combinedMatrix()); if (state.isOpacityDirty()) program()->setUniformValue(m_id_opacity, state.opacity()); } private: int m_id_matrix; int m_id_opacity; }; \endcode \note All classes with QSG prefix should be used solely on the scene graph's rendering thread. See \l {Scene Graph and Rendering} for more information. */ /*! Creates a new QSGMaterialShader. */ QSGMaterialShader::QSGMaterialShader() : d_ptr(new QSGMaterialShaderPrivate) { } /*! \internal */ QSGMaterialShader::QSGMaterialShader(QSGMaterialShaderPrivate &dd) : d_ptr(&dd) { } /*! \internal */ QSGMaterialShader::~QSGMaterialShader() { } /*! \fn char const *const *QSGMaterialShader::attributeNames() const Returns a zero-terminated array describing the names of the attributes used in the vertex shader. This function is called when the shader is compiled to specify which attributes exist. The order of the attribute names defines the attribute register position in the vertex shader. */ #if QT_CONFIG(opengl) /*! \fn const char *QSGMaterialShader::vertexShader() const Called when the shader is being initialized to get the vertex shader source code. The contents returned from this function should never change. */ const char *QSGMaterialShader::vertexShader() const { Q_D(const QSGMaterialShader); return d->loadShaderSource(QOpenGLShader::Vertex); } /*! \fn const char *QSGMaterialShader::fragmentShader() const Called when the shader is being initialized to get the fragment shader source code. The contents returned from this function should never change. */ const char *QSGMaterialShader::fragmentShader() const { Q_D(const QSGMaterialShader); return d->loadShaderSource(QOpenGLShader::Fragment); } /*! \fn QOpenGLShaderProgram *QSGMaterialShader::program() Returns the shader program used by this QSGMaterialShader. */ #endif /*! \fn void QSGMaterialShader::initialize() Reimplement this function to do one-time initialization when the shader program is compiled. The OpenGL shader program is compiled and linked, but not bound, when this function is called. */ /*! This function is called by the scene graph to indicate that geometry is about to be rendered using this shader. State that is global for all uses of the shader, independent of the geometry that is being drawn, can be setup in this function. */ void QSGMaterialShader::activate() { } /*! This function is called by the scene graph to indicate that geometry will no longer to be rendered using this shader. */ void QSGMaterialShader::deactivate() { } /*! This function is called by the scene graph before geometry is rendered to make sure the shader is in the right state. The current rendering \a state is passed from the scene graph. If the state indicates that any state is dirty, the updateState implementation must update accordingly for the geometry to render correctly. The subclass specific state, such as the color of a flat color material, should be extracted from \a newMaterial to update the color uniforms accordingly. The \a oldMaterial can be used to minimze state changes when updating material states. The \a oldMaterial is 0 if this shader was just activated. \sa activate(), deactivate() */ void QSGMaterialShader::updateState(const RenderState & /* state */, QSGMaterial * /* newMaterial */, QSGMaterial * /* oldMaterial */) { } #if QT_CONFIG(opengl) /*! Sets the GLSL source file for the shader stage \a type to \a sourceFile. The default implementation of the vertexShader() and fragmentShader() functions will load the source files set by this function. This function is useful when you have a single source file for a given shader stage. If your shader consists of multiple source files then use setShaderSourceFiles() \sa setShaderSourceFiles(), vertexShader(), fragmentShader() */ void QSGMaterialShader::setShaderSourceFile(QOpenGLShader::ShaderType type, const QString &sourceFile) { Q_D(QSGMaterialShader); d->m_sourceFiles[type] = (QStringList() << sourceFile); } /*! Sets the GLSL source files for the shader stage \a type to \a sourceFiles. The default implementation of the vertexShader() and fragmentShader() functions will load the source files set by this function in the order given. \sa setShaderSourceFile(), vertexShader(), fragmentShader() */ void QSGMaterialShader::setShaderSourceFiles(QOpenGLShader::ShaderType type, const QStringList &sourceFiles) { Q_D(QSGMaterialShader); d->m_sourceFiles[type] = sourceFiles; } /*! This function is called when the shader is initialized to compile the actual QOpenGLShaderProgram. Do not call it explicitly. The default implementation will extract the vertexShader() and fragmentShader() and bind the names returned from attributeNames() to consecutive vertex attribute registers starting at 0. */ void QSGMaterialShader::compile() { Q_ASSERT_X(!m_program.isLinked(), "QSGSMaterialShader::compile()", "Compile called multiple times!"); program()->addCacheableShaderFromSourceCode(QOpenGLShader::Vertex, vertexShader()); program()->addCacheableShaderFromSourceCode(QOpenGLShader::Fragment, fragmentShader()); char const *const *attr = attributeNames(); #ifndef QT_NO_DEBUG int maxVertexAttribs = 0; QOpenGLFunctions *funcs = QOpenGLContext::currentContext()->functions(); funcs->glGetIntegerv(GL_MAX_VERTEX_ATTRIBS, &maxVertexAttribs); for (int i = 0; attr[i]; ++i) { if (i >= maxVertexAttribs) { qFatal("List of attribute names is either too long or not null-terminated.\n" "Maximum number of attributes on this hardware is %i.\n" "Vertex shader:\n%s\n" "Fragment shader:\n%s\n", maxVertexAttribs, vertexShader(), fragmentShader()); } if (*attr[i]) program()->bindAttributeLocation(attr[i], i); } #else for (int i = 0; attr[i]; ++i) { if (*attr[i]) program()->bindAttributeLocation(attr[i], i); } #endif if (!program()->link()) { qWarning("QSGMaterialShader: Shader compilation failed:"); qWarning() << program()->log(); } } #endif /*! \class QSGMaterialShader::RenderState \brief The QSGMaterialShader::RenderState encapsulates the current rendering state during a call to QSGMaterialShader::updateState(). \inmodule QtQuick The render state contains a number of accessors that the shader needs to respect in order to conform to the current state of the scene graph. The instance is only valid inside a call to QSGMaterialShader::updateState() and should not be used outisde this function. */ /*! \enum QSGMaterialShader::RenderState::DirtyState \value DirtyMatrix Used to indicate that the matrix has changed and must be updated. \value DirtyOpacity Used to indicate that the opacity has changed and must be updated. \value DirtyCachedMaterialData Used to indicate that the cached material data have changed and must be updated. \value DirtyAll Used to indicate that everything needs to be updated. */ /*! \fn bool QSGMaterialShader::RenderState::isMatrixDirty() const Returns \c true if the dirtyStates() contain the dirty matrix state, otherwise returns \c false. */ /*! \fn bool QSGMaterialShader::RenderState::isOpacityDirty() const Returns \c true if the dirtyStates() contains the dirty opacity state, otherwise returns \c false. */ /*! \fn bool QSGMaterialShader::RenderState::isCachedMaterialDataDirty() const Returns \c true if the dirtyStates() contains the dirty cached material state, otherwise returns \c false. */ /*! \fn QSGMaterialShader::RenderState::DirtyStates QSGMaterialShader::RenderState::dirtyStates() const Returns which rendering states that have changed and needs to be updated for geometry rendered with this material to conform to the current rendering state. */ /*! Returns the accumulated opacity to be used for rendering. */ float QSGMaterialShader::RenderState::opacity() const { Q_ASSERT(m_data); return static_cast(m_data)->currentOpacity(); } /*! Returns the modelview determinant to be used for rendering. */ float QSGMaterialShader::RenderState::determinant() const { Q_ASSERT(m_data); return static_cast(m_data)->determinant(); } /*! Returns the matrix combined of modelview matrix and project matrix. */ QMatrix4x4 QSGMaterialShader::RenderState::combinedMatrix() const { Q_ASSERT(m_data); return static_cast(m_data)->currentCombinedMatrix(); } /*! Returns the ratio between physical pixels and device-independent pixels to be used for rendering. */ float QSGMaterialShader::RenderState::devicePixelRatio() const { Q_ASSERT(m_data); return static_cast(m_data)->devicePixelRatio(); } /*! Returns the model view matrix. If the material has the RequiresFullMatrix flag set, this is guaranteed to be the complete transform matrix calculated from the scenegraph. However, if this flag is not set, the renderer may choose to alter this matrix. For example, it may pre-transform vertices on the CPU and set this matrix to identity. In a situation such as the above, it is still possible to retrieve the actual matrix determinant by setting the RequiresDeterminant flag in the material and calling the determinant() accessor. */ QMatrix4x4 QSGMaterialShader::RenderState::modelViewMatrix() const { Q_ASSERT(m_data); return static_cast(m_data)->currentModelViewMatrix(); } /*! Returns the projection matrix. */ QMatrix4x4 QSGMaterialShader::RenderState::projectionMatrix() const { Q_ASSERT(m_data); return static_cast(m_data)->currentProjectionMatrix(); } /*! Returns the viewport rect of the surface being rendered to. */ QRect QSGMaterialShader::RenderState::viewportRect() const { Q_ASSERT(m_data); return static_cast(m_data)->viewportRect(); } /*! Returns the device rect of the surface being rendered to */ QRect QSGMaterialShader::RenderState::deviceRect() const { Q_ASSERT(m_data); return static_cast(m_data)->deviceRect(); } #if QT_CONFIG(opengl) /*! Returns the QOpenGLContext that is being used for rendering */ QOpenGLContext *QSGMaterialShader::RenderState::context() const { // Only the QSGDefaultRenderContext will have an OpenGL Context to query auto openGLRenderContext = static_cast(static_cast(m_data)->context()); if (openGLRenderContext != nullptr) return openGLRenderContext->openglContext(); else return nullptr; } #endif QT_END_NAMESPACE