QMaterial Class

Detailed Description

QMaterial provides a way to specify the rendering of an entity. Any aspect can define its own subclass of QMaterial so that a Material can be used to describe a visual element; for example, the way sound should reflect off an element, the temperature of a surface, and so on.

In itself, a QMaterial doesn't do anything. It's only when it references a QEffect node that a QMaterial becomes useful.

In practice, it often happens that a single QEffect is being referenced by several QMaterial components. This allows to only create the effect, techniques, passes and shaders once while allowing to specify the material by adding QParameter instances.

A QParameter defined on a QMaterial overrides parameter (of the same name) defined in a QEffect, QTechnique and QRenderPass, but are overridden by parameter in QRenderPassFilter and QTechniqueFilter.

 QMaterial *material1 = new QMaterial();
 QMaterial *material2 = new QMaterial();

 // Create effect, technique, render pass and shader
 QEffect *effect = new QEffect();
 QTechnique *gl3Technique = new QTechnique();
 QRenderPass *gl3Pass = new QRenderPass();
 QShaderProgram *glShader = new QShaderProgram();

 // Set the shader on the render pass
 gl3Pass->setShaderProgram(glShader);

 // Add the pass to the technique
 gl3Technique->addRenderPass(gl3Pass);

 // Set the targeted GL version for the technique
 gl3Technique->graphicsApiFilter()->setApi(QGraphicsApiFilter::OpenGL);
 gl3Technique->graphicsApiFilter()->setMajorVersion(3);
 gl3Technique->graphicsApiFilter()->setMinorVersion(1);
 gl3Technique->graphicsApiFilter()->setProfile(QGraphicsApiFilter::CoreProfile);

 // Add the technique to the effect
 effect->addTechnique(gl3Technique);

 // Set the effect on the materials
 material1->setEffect(effect);
 material2->setEffect(effect);

 // Set different parameters on the materials
 const QString parameterName = QStringLiteral("color");
 material1->addParameter(new QParameter(parameterName, QColor::fromRgbF(0.0f, 1.0f, 0.0f, 1.0f)));
 material2->addParameter(new QParameter(parameterName, QColor::fromRgbF(1.0f, 1.0f, 1.0f, 1.0f)));