QGLShaderProgram¶

The QGLShaderProgram class allows OpenGL shader programs to be linked and used. More…

New in version 4.6.

Synopsis¶

Functions¶

def addShader (shader)
def addShaderFromSourceCode (type, source)
def addShaderFromSourceCode (type, source)
def addShaderFromSourceCode (type, source)
def addShaderFromSourceFile (type, fileName)
def attributeLocation (name)
def attributeLocation (name)
def attributeLocation (name)
def bind ()
def bindAttributeLocation (name, location)
def bindAttributeLocation (name, location)
def bindAttributeLocation (name, location)
def disableAttributeArray (location)
def disableAttributeArray (name)
def enableAttributeArray (location)
def enableAttributeArray (name)
def geometryInputType ()
def geometryOutputType ()
def geometryOutputVertexCount ()
def isLinked ()
def log ()
def maxGeometryOutputVertices ()
def programId ()
def release ()
def removeAllShaders ()
def removeShader (shader)
def setAttributeArray2D (location, values[, stride=0])
def setAttributeArray2D (name, values[, stride=0])
def setAttributeArray3D (location, values[, stride=0])
def setAttributeArray3D (name, values[, stride=0])
def setAttributeArray4D (location, values[, stride=0])
def setAttributeArray4D (name, values[, stride=0])
def setAttributeBuffer (location, type, offset, tupleSize[, stride=0])
def setAttributeBuffer (name, type, offset, tupleSize[, stride=0])
def setAttributeValue (location, value)
def setAttributeValue (location, value)
def setAttributeValue (location, value)
def setAttributeValue (location, value)
def setAttributeValue (location, value)
def setAttributeValue (location, x, y)
def setAttributeValue (location, x, y, z)
def setAttributeValue (location, x, y, z, w)
def setAttributeValue (name, value)
def setAttributeValue (name, value)
def setAttributeValue (name, value)
def setAttributeValue (name, value)
def setAttributeValue (name, value)
def setAttributeValue (name, x, y)
def setAttributeValue (name, x, y, z)
def setAttributeValue (name, x, y, z, w)
def setGeometryInputType (inputType)
def setGeometryOutputType (outputType)
def setGeometryOutputVertexCount (count)
def setUniformValue (location, color)
def setUniformValue (location, point)
def setUniformValue (location, point)
def setUniformValue (location, size)
def setUniformValue (location, size)
def setUniformValue (location, value)
def setUniformValue (location, value)
def setUniformValue (location, value)
def setUniformValue (location, value)
def setUniformValue (location, value)
def setUniformValue (location, value)
def setUniformValue (location, value)
def setUniformValue (location, value)
def setUniformValue (location, value)
def setUniformValue (location, value)
def setUniformValue (location, value)
def setUniformValue (location, value)
def setUniformValue (location, value)
def setUniformValue (location, value)
def setUniformValue (location, value)
def setUniformValue (location, value)
def setUniformValue (location, x, y)
def setUniformValue (location, x, y, z)
def setUniformValue (location, x, y, z, w)
def setUniformValue (name, color)
def setUniformValue (name, point)
def setUniformValue (name, point)
def setUniformValue (name, size)
def setUniformValue (name, size)
def setUniformValue (name, value)
def setUniformValue (name, value)
def setUniformValue (name, value)
def setUniformValue (name, value)
def setUniformValue (name, value)
def setUniformValue (name, value)
def setUniformValue (name, value)
def setUniformValue (name, value)
def setUniformValue (name, value)
def setUniformValue (name, value)
def setUniformValue (name, value)
def setUniformValue (name, value)
def setUniformValue (name, value)
def setUniformValue (name, value)
def setUniformValue (name, value)
def setUniformValue (name, value)
def setUniformValue (name, x, y)
def setUniformValue (name, x, y, z)
def setUniformValue (name, x, y, z, w)
def setUniformValueArray2D (location, values)
def setUniformValueArray2D (name, values)
def setUniformValueArray2x2 (location, values)
def setUniformValueArray2x2 (name, values)
def setUniformValueArray2x3 (location, values)
def setUniformValueArray2x3 (name, values)
def setUniformValueArray2x4 (location, values)
def setUniformValueArray2x4 (name, values)
def setUniformValueArray3D (location, values)
def setUniformValueArray3D (name, values)
def setUniformValueArray3x2 (location, values)
def setUniformValueArray3x2 (name, values)
def setUniformValueArray3x3 (location, values)
def setUniformValueArray3x3 (name, values)
def setUniformValueArray3x4 (location, values)
def setUniformValueArray3x4 (name, values)
def setUniformValueArray4D (location, values)
def setUniformValueArray4D (name, values)
def setUniformValueArray4x2 (location, values)
def setUniformValueArray4x2 (name, values)
def setUniformValueArray4x3 (location, values)
def setUniformValueArray4x3 (name, values)
def setUniformValueArray4x4 (location, values)
def setUniformValueArray4x4 (name, values)
def setUniformValueArrayInt (location, values)
def setUniformValueArrayInt (name, values)
def setUniformValueArrayUint (location, values)
def setUniformValueArrayUint (name, values)
def shaders ()
def uniformLocation (name)
def uniformLocation (name)
def uniformLocation (name)

Virtual functions¶

def link ()

Static functions¶

def hasOpenGLShaderPrograms ([context=None])

Detailed Description¶

Introduction¶

This class supports shader programs written in the OpenGL Shading Language (GLSL) and in the OpenGL/ES Shading Language (GLSL/ES).

QGLShader and QGLShaderProgram shelter the programmer from the details of compiling and linking vertex and fragment shaders.

The following example creates a vertex shader program using the supplied source code . Once compiled and linked, the shader program is activated in the current QGLContext by calling bind() :
shader = QGLShader(QGLShader.Vertex)
shader.compileSourceCode(code)

program = QGLShaderProgram(context)
program.addShader(shader)
program.link()

program.bind()

Writing Portable Shaders¶

Shader programs can be difficult to reuse across OpenGL implementations because of varying levels of support for standard vertex attributes and uniform variables. In particular, GLSL/ES lacks all of the standard variables that are present on desktop OpenGL systems: gl_Vertex , gl_Normal , gl_Color , and so on. Desktop OpenGL lacks the variable qualifiers highp , mediump , and lowp .

The QGLShaderProgram class makes the process of writing portable shaders easier by prefixing all shader programs with the following lines on desktop OpenGL:
#define highp
#define mediump
#define lowp
This makes it possible to run most GLSL/ES shader programs on desktop systems. The programmer should restrict themselves to just features that are present in GLSL/ES, and avoid standard variable names that only work on the desktop.

Simple Shader Example¶

program.addShaderFromSourceCode(QGLShader.Vertex,
    "attribute highp vec4 vertex\n" \
    "attribute mediump mat4 matrix\n" \
    "void main(void)\n" \
    "{\n" \
    "   gl_Position = matrix * vertex\n" \
    "}")
program.addShaderFromSourceCode(QGLShader.Fragment,
    "uniform mediump vec4 color\n" \
    "void main(void)\n" \
    "{\n" \
    "   gl_FragColor = color\n" \
    "}")
program.link()
program.bind()

vertexLocation = program.attributeLocation("vertex")
matrixLocation = program.attributeLocation("matrix")
colorLocation = program.uniformLocation("color")

With the above shader program active, we can draw a green triangle as follows:

triangleVertices = (
    60.0f,  10.0f,  0.0f,
    110.0f, 110.0f, 0.0f,
    10.0f,  110.0f, 0.0f)

color = QColor(0, 255, 0, 255)

pmvMatrix = QMatrix4x4()
pmvMatrix.ortho(self.rect())

program.enableAttributeArray(vertexLocation)
program.setAttributeArray(vertexLocation, triangleVertices, 3)
program.setUniformValue(matrixLocation, pmvMatrix)
program.setUniformValue(colorLocation, color)

glDrawArrays(GL_TRIANGLES, 0, 3)

program.disableAttributeArray(vertexLocation)

Binary Shaders and Programs¶

Binary shaders may be specified using glShaderBinary() on the return value from shaderId() . The QGLShader instance containing the binary can then be added to the shader program with addShader() and linked in the usual fashion with link() .

Binary programs may be specified using glProgramBinaryOES() on the return value from programId() . Then the application should call link() , which will notice that the program has already been specified and linked, allowing other operations to be performed on the shader program.

Note

This class has been deprecated in favor of QOpenGLShaderProgram .

See also

QGLShader

class PySide2.QtOpenGL.QGLShaderProgram([parent=None])¶

PySide2.QtOpenGL.QGLShaderProgram(context[, parent=None])

param parent:

PySide2.QtCore.QObject

param context:

PySide2.QtOpenGL.QGLContext

Constructs a new shader program and attaches it to parent . The program will be invalid until addShader() is called.

The shader program will be associated with the current QGLContext .

See also

addShader()

Constructs a new shader program and attaches it to parent . The program will be invalid until addShader() is called.

The shader program will be associated with context .

See also

addShader()

PySide2.QtOpenGL.QGLShaderProgram.addShader(shader)¶

Parameters:: shader – PySide2.QtOpenGL.QGLShader
Return type:: bool

Adds a compiled shader to this shader program. Returns true if the shader could be added, or false otherwise.

Ownership of the shader object remains with the caller. It will not be deleted when this QGLShaderProgram instance is deleted. This allows the caller to add the same shader to multiple shader programs.

PySide2.QtOpenGL.QGLShaderProgram.addShaderFromSourceCode(type, source)¶

Parameters:

type – ShaderType
source – PySide2.QtCore.QByteArray

Return type:

bool

PySide2.QtOpenGL.QGLShaderProgram.addShaderFromSourceCode(type, source)

Parameters:

type – ShaderType
source – str

Return type:

bool

Compiles source as a shader of the specified type and adds it to this shader program. Returns true if compilation was successful, false otherwise. The compilation errors and warnings will be made available via log() .

This function is intended to be a short-cut for quickly adding vertex and fragment shaders to a shader program without creating an instance of QGLShader first.

PySide2.QtOpenGL.QGLShaderProgram.addShaderFromSourceCode(type, source)

Parameters:

type – ShaderType
source – str

Return type:

bool

PySide2.QtOpenGL.QGLShaderProgram.addShaderFromSourceFile(type, fileName)¶

Parameters:

type – ShaderType
fileName – str

Return type:

bool

Compiles the contents of fileName as a shader of the specified type and adds it to this shader program. Returns true if compilation was successful, false otherwise. The compilation errors and warnings will be made available via log() .

This function is intended to be a short-cut for quickly adding vertex and fragment shaders to a shader program without creating an instance of QGLShader first.

PySide2.QtOpenGL.QGLShaderProgram.attributeLocation(name)¶

Parameters:: name – PySide2.QtCore.QByteArray
Return type:: int

PySide2.QtOpenGL.QGLShaderProgram.attributeLocation(name)

Parameters:: name – str
Return type:: int

PySide2.QtOpenGL.QGLShaderProgram.attributeLocation(name)

Parameters:: name – str
Return type:: int

Returns the location of the attribute name within this shader program’s parameter list. Returns -1 if name is not a valid attribute for this shader program.

PySide2.QtOpenGL.QGLShaderProgram.bind()¶

Return type:: bool

Binds this shader program to the active QGLContext and makes it the current shader program. Any previously bound shader program is released. This is equivalent to calling glUseProgram() on programId() . Returns true if the program was successfully bound; false otherwise. If the shader program has not yet been linked, or it needs to be re-linked, this function will call link() .

See also

link() release()

PySide2.QtOpenGL.QGLShaderProgram.bindAttributeLocation(name, location)¶

Parameters:

name – PySide2.QtCore.QByteArray
location – int

PySide2.QtOpenGL.QGLShaderProgram.bindAttributeLocation(name, location)

Parameters:

name – str
location – int

PySide2.QtOpenGL.QGLShaderProgram.bindAttributeLocation(name, location)

Parameters:

name – str
location – int

Binds the attribute name to the specified location . This function can be called before or after the program has been linked. Any attributes that have not been explicitly bound when the program is linked will be assigned locations automatically.

When this function is called after the program has been linked, the program will need to be relinked for the change to take effect.

See also

attributeLocation()

PySide2.QtOpenGL.QGLShaderProgram.disableAttributeArray(name)¶

Parameters:: name – str

This is an overloaded function.

Disables the vertex array called name in this shader program that was enabled by a previous call to enableAttributeArray() .

PySide2.QtOpenGL.QGLShaderProgram.disableAttributeArray(location)

Parameters:: location – int

Disables the vertex array at location in this shader program that was enabled by a previous call to enableAttributeArray() .

PySide2.QtOpenGL.QGLShaderProgram.enableAttributeArray(name)¶

Parameters:: name – str

This is an overloaded function.

Enables the vertex array called name in this shader program so that the value set by setAttributeArray() on name will be used by the shader program.

PySide2.QtOpenGL.QGLShaderProgram.enableAttributeArray(location)

Parameters:: location – int

Enables the vertex array at location in this shader program so that the value set by setAttributeArray() on location will be used by the shader program.

PySide2.QtOpenGL.QGLShaderProgram.geometryInputType()¶

Return type:: GLenum

Returns the geometry shader input type, if active.

This parameter takes effect the next time the program is linked.

See also

setGeometryInputType()

PySide2.QtOpenGL.QGLShaderProgram.geometryOutputType()¶

Return type:: GLenum

Returns the geometry shader output type, if active.

This parameter takes effect the next time the program is linked.

See also

setGeometryOutputType()

PySide2.QtOpenGL.QGLShaderProgram.geometryOutputVertexCount()¶

Return type:: int

Returns the maximum number of vertices the current geometry shader program will produce, if active.

This parameter takes effect the ntext time the program is linked.

See also

setGeometryOutputVertexCount()

static PySide2.QtOpenGL.QGLShaderProgram.hasOpenGLShaderPrograms([context=None])¶

Parameters:: context – PySide2.QtOpenGL.QGLContext
Return type:: bool

Returns true if shader programs written in the OpenGL Shading Language (GLSL) are supported on this system; false otherwise.

The context is used to resolve the GLSL extensions. If context is None , then currentContext() is used.

PySide2.QtOpenGL.QGLShaderProgram.isLinked()¶

Return type:: bool

Returns true if this shader program has been linked; false otherwise.

See also

link()

PySide2.QtOpenGL.QGLShaderProgram.link()¶

Return type:: bool

Links together the shaders that were added to this program with addShader() . Returns true if the link was successful or false otherwise. If the link failed, the error messages can be retrieved with log() .

Subclasses can override this function to initialize attributes and uniform variables for use in specific shader programs.

If the shader program was already linked, calling this function again will force it to be re-linked.

See also

addShader() log()

PySide2.QtOpenGL.QGLShaderProgram.log()¶

Return type:: str

Returns the errors and warnings that occurred during the last link() or addShader() with explicitly specified source code.

See also

link()

PySide2.QtOpenGL.QGLShaderProgram.maxGeometryOutputVertices()¶

Return type:: int

Returns the hardware limit for how many vertices a geometry shader can output.

See also

setGeometryOutputVertexCount()

PySide2.QtOpenGL.QGLShaderProgram.programId()¶

Return type:: GLuint

Returns the OpenGL identifier associated with this shader program.

See also

shaderId()

PySide2.QtOpenGL.QGLShaderProgram.release()¶: Releases the active shader program from the current QGLContext . This is equivalent to calling glUseProgram(0) .

See also

bind()

PySide2.QtOpenGL.QGLShaderProgram.removeAllShaders()¶: Removes all of the shaders that were added to this program previously. The QGLShader objects for the shaders will not be deleted if they were constructed externally. QGLShader objects that are constructed internally by QGLShaderProgram will be deleted.

See also

addShader() removeShader()

PySide2.QtOpenGL.QGLShaderProgram.removeShader(shader)¶

Parameters:: shader – PySide2.QtOpenGL.QGLShader

Removes shader from this shader program. The object is not deleted.

The shader program must be valid in the current QGLContext .

PySide2.QtOpenGL.QGLShaderProgram.setAttributeArray2D(name, values[, stride=0])¶

Parameters:

name – str
values – PySide2.QtGui.QVector2D
stride – int

This is an overloaded function.

Sets an array of 2D vertex values on the attribute called name in this shader program. The stride indicates the number of bytes between vertices. A default stride value of zero indicates that the vertices are densely packed in values .

The array will become active when enableAttributeArray() is called on name . Otherwise the value specified with setAttributeValue() for name will be used.

PySide2.QtOpenGL.QGLShaderProgram.setAttributeArray2D(location, values[, stride=0])

Parameters:

location – int
values – PySide2.QtGui.QVector2D
stride – int

Sets an array of 2D vertex values on the attribute at location in this shader program. The stride indicates the number of bytes between vertices. A default stride value of zero indicates that the vertices are densely packed in values .

The array will become active when enableAttributeArray() is called on the location . Otherwise the value specified with setAttributeValue() for location will be used.

PySide2.QtOpenGL.QGLShaderProgram.setAttributeArray3D(name, values[, stride=0])¶

Parameters:

name – str
values – PySide2.QtGui.QVector3D
stride – int

This is an overloaded function.

Sets an array of 3D vertex values on the attribute called name in this shader program. The stride indicates the number of bytes between vertices. A default stride value of zero indicates that the vertices are densely packed in values .

The array will become active when enableAttributeArray() is called on name . Otherwise the value specified with setAttributeValue() for name will be used.

PySide2.QtOpenGL.QGLShaderProgram.setAttributeArray3D(location, values[, stride=0])

Parameters:

location – int
values – PySide2.QtGui.QVector3D
stride – int

Sets an array of 3D vertex values on the attribute at location in this shader program. The stride indicates the number of bytes between vertices. A default stride value of zero indicates that the vertices are densely packed in values .

The array will become active when enableAttributeArray() is called on the location . Otherwise the value specified with setAttributeValue() for location will be used.

PySide2.QtOpenGL.QGLShaderProgram.setAttributeArray4D(location, values[, stride=0])¶

Parameters:

location – int
values – PySide2.QtGui.QVector4D
stride – int

Sets an array of 4D vertex values on the attribute at location in this shader program. The stride indicates the number of bytes between vertices. A default stride value of zero indicates that the vertices are densely packed in values .

The array will become active when enableAttributeArray() is called on the location . Otherwise the value specified with setAttributeValue() for location will be used.

PySide2.QtOpenGL.QGLShaderProgram.setAttributeArray4D(name, values[, stride=0])

Parameters:

name – str
values – PySide2.QtGui.QVector4D
stride – int

This is an overloaded function.

Sets an array of 4D vertex values on the attribute called name in this shader program. The stride indicates the number of bytes between vertices. A default stride value of zero indicates that the vertices are densely packed in values .

The array will become active when enableAttributeArray() is called on name . Otherwise the value specified with setAttributeValue() for name will be used.

PySide2.QtOpenGL.QGLShaderProgram.setAttributeBuffer(name, type, offset, tupleSize[, stride=0])¶

Parameters:

name – str
type – GLenum
offset – int
tupleSize – int
stride – int

This is an overloaded function.

Sets an array of vertex values on the attribute called name in this shader program, starting at a specific offset in the currently bound vertex buffer. The stride indicates the number of bytes between vertices. A default stride value of zero indicates that the vertices are densely packed in the value array.

The type indicates the type of elements in the vertex value array, usually GL_FLOAT , GL_UNSIGNED_BYTE , etc. The tupleSize indicates the number of components per vertex: 1, 2, 3, or 4.

The array will become active when enableAttributeArray() is called on the name . Otherwise the value specified with setAttributeValue() for name will be used.

See also

setAttributeArray()

PySide2.QtOpenGL.QGLShaderProgram.setAttributeBuffer(location, type, offset, tupleSize[, stride=0])

Parameters:

location – int
type – GLenum
offset – int
tupleSize – int
stride – int

Sets an array of vertex values on the attribute at location in this shader program, starting at a specific offset in the currently bound vertex buffer. The stride indicates the number of bytes between vertices. A default stride value of zero indicates that the vertices are densely packed in the value array.

The type indicates the type of elements in the vertex value array, usually GL_FLOAT , GL_UNSIGNED_BYTE , etc. The tupleSize indicates the number of components per vertex: 1, 2, 3, or 4.

The array will become active when enableAttributeArray() is called on the location . Otherwise the value specified with setAttributeValue() for location will be used.

Note

Normalization will be enabled. If this is not desired, call glVertexAttribPointer directly though QGLFunctions .

See also

setAttributeArray()

PySide2.QtOpenGL.QGLShaderProgram.setAttributeValue(location, value)¶

Parameters:

location – int
value – PySide2.QtGui.QVector4D

PySide2.QtOpenGL.QGLShaderProgram.setAttributeValue(location, value)

Parameters:

location – int
value – PySide2.QtGui.QVector3D

PySide2.QtOpenGL.QGLShaderProgram.setAttributeValue(location, value)

Parameters:

location – int
value – PySide2.QtGui.QVector2D

PySide2.QtOpenGL.QGLShaderProgram.setAttributeValue(location, value)

Parameters:

location – int
value – PySide2.QtGui.QColor

PySide2.QtOpenGL.QGLShaderProgram.setAttributeValue(location, x, y, z, w)

Parameters:

location – int
x – GLfloat
y – GLfloat
z – GLfloat
w – GLfloat

Sets the attribute at location in the current context to the 4D vector (x , y , z , w ).

See also

setUniformValue()

PySide2.QtOpenGL.QGLShaderProgram.setAttributeValue(location, x, y, z)

Parameters:

location – int
x – GLfloat
y – GLfloat
z – GLfloat

Sets the attribute at location in the current context to the 3D vector (x , y , z ).

See also

setUniformValue()

PySide2.QtOpenGL.QGLShaderProgram.setAttributeValue(location, x, y)

Parameters:

location – int
x – GLfloat
y – GLfloat

Sets the attribute at location in the current context to the 2D vector (x , y ).

See also

setUniformValue()

PySide2.QtOpenGL.QGLShaderProgram.setAttributeValue(location, value)

Parameters:

location – int
value – GLfloat

Sets the attribute at location in the current context to value .

See also

setUniformValue()

PySide2.QtOpenGL.QGLShaderProgram.setAttributeValue(name, value)

Parameters:

name – str
value – PySide2.QtGui.QVector3D

PySide2.QtOpenGL.QGLShaderProgram.setAttributeValue(name, value)

Parameters:

name – str
value – PySide2.QtGui.QVector4D

PySide2.QtOpenGL.QGLShaderProgram.setAttributeValue(name, value)

Parameters:

name – str
value – GLfloat

This is an overloaded function.

Sets the attribute called name in the current context to value .

See also

setUniformValue()

PySide2.QtOpenGL.QGLShaderProgram.setAttributeValue(name, x, y)

Parameters:

name – str
x – GLfloat
y – GLfloat

This is an overloaded function.

Sets the attribute called name in the current context to the 2D vector (x , y ).

See also

setUniformValue()

PySide2.QtOpenGL.QGLShaderProgram.setAttributeValue(name, x, y, z)

Parameters:

name – str
x – GLfloat
y – GLfloat
z – GLfloat

This is an overloaded function.

Sets the attribute called name in the current context to the 3D vector (x , y , z ).

See also

setUniformValue()

PySide2.QtOpenGL.QGLShaderProgram.setAttributeValue(name, value)

Parameters:

name – str
value – PySide2.QtGui.QColor

PySide2.QtOpenGL.QGLShaderProgram.setAttributeValue(name, value)

Parameters:

name – str
value – PySide2.QtGui.QVector2D

PySide2.QtOpenGL.QGLShaderProgram.setAttributeValue(name, x, y, z, w)

Parameters:

name – str
x – GLfloat
y – GLfloat
z – GLfloat
w – GLfloat

This is an overloaded function.

Sets the attribute called name in the current context to the 4D vector (x , y , z , w ).

See also

setUniformValue()

PySide2.QtOpenGL.QGLShaderProgram.setGeometryInputType(inputType)¶

Parameters:: inputType – GLenum

Sets the input type from inputType .

This parameter takes effect the next time the program is linked.

See also

geometryInputType()

PySide2.QtOpenGL.QGLShaderProgram.setGeometryOutputType(outputType)¶

Parameters:: outputType – GLenum

Sets the output type from the geometry shader, if active, to outputType .

This parameter takes effect the next time the program is linked.

See also

geometryOutputType()

PySide2.QtOpenGL.QGLShaderProgram.setGeometryOutputVertexCount(count)¶

Parameters:: count – int

Sets the maximum number of vertices the current geometry shader program will produce, if active, to count .

This parameter takes effect the next time the program is linked.

See also

geometryOutputVertexCount()

PySide2.QtOpenGL.QGLShaderProgram.setUniformValue(location, value)¶

Parameters:

location – int
value – GLfloat

Sets the uniform variable at location in the current context to value .

See also