class TestCanvas(Canvas):
def __init__(self):
with open("vertex.glsl","r") as f:
self.vertexShaderSource = f.read()
with open("fragment.glsl","r") as f:
self.fragmentShaderSource = f.read()
if self.vertexShaderSource is None:
raise Exception("Could not load the source for the vertex shader")
if self.fragmentShaderSource is None:
raise Exception("Could not load the source for the fragment shader")
super(TestCanvas,self).__init__()
def setupGL(self):
self.program = QOpenGLShaderProgram(self.context())
info("PROGRAM",self.program)
# addShaderFromSourceCode() only returns a bool telling whether everything went well
if self.program.addShaderFromSourceCode(QOpenGLShader.Vertex, self.vertexShaderSource):
info("VERTEX SHADER","Managed to load and parse the vertex shader")
if self.program.addShaderFromSourceCode(QOpenGLShader.Fragment, self.fragmentShaderSource):
info("FRAGMENT SHADER","Managed to load and parse the fragment shader")
# Compile and bind the shader program to the current context
self.program.link()
self.program.bind()
# Bind the shader attribute to a python variable
self.somePosition = self.gl.glGetAttribLocation(self.program.programId(), "somePosition")
# Tell GL that whenever we run glClear, this is the color that
# should be used. We only need to do this once.
self.gl.glClearColor(0.1, 0.1, 0.1, 1.0)
self.dumpGLLogMessages("setupGL()")
def paintGL(self):
self.gl.glClear(self.gl.GL_COLOR_BUFFER_BIT | self.gl.GL_DEPTH_BUFFER_BIT)
# Assign a value to the shader parameter
self.gl.glVertexAttrib3f(self.somePosition, 0.5, 0.5, 0.0)
# Mode, starting at vertex number, number of vertices to draw
self.gl.glDrawArrays(self.gl.GL_POINTS,0,1)
self.dumpGLLogMessages("paintGL()")
def resizeGL(self, width, height):
pass
class TestCanvas(Canvas):
def __init__(self):
with open("vertex.glsl", "r") as f:
self.vertexShaderSource = f.read()
with open("fragment.glsl", "r") as f:
self.fragmentShaderSource = f.read()
if self.vertexShaderSource is None:
raise Exception("Could not load the source for the vertex shader")
if self.fragmentShaderSource is None:
raise Exception(
"Could not load the source for the fragment shader")
super(TestCanvas, self).__init__()
def setupGL(self):
self.program = QOpenGLShaderProgram(self.context())
info("PROGRAM", self.program)
# addShaderFromSourceCode() only returns a bool telling whether everything went well
if self.program.addShaderFromSourceCode(QOpenGLShader.Vertex,
self.vertexShaderSource):
info("VERTEX SHADER",
"Managed to load and parse the vertex shader")
if self.program.addShaderFromSourceCode(QOpenGLShader.Fragment,
self.fragmentShaderSource):
info("FRAGMENT SHADER",
"Managed to load and parse the fragment shader")
# Compile and bind the shader program to the current context
self.program.link()
self.program.bind()
# Bind the shader attribute to a python variable
self.somePosition = self.gl.glGetAttribLocation(
self.program.programId(), "somePosition")
# Use array rather than list in order to get control over actual data size
self.vertices = array.array(
'f',
[-0.5, -0.5, 0.0, 0.5, 0.5, 0.0, 0.5, -0.5, 0.0, 0.0, 0.0, 0.0])
# Buffer info returns a tuple where the second part is number of elements in the array
self.verticesLength = self.vertices.buffer_info()[1]
# Size in bytes for each element
self.verticesItemSize = self.vertices.itemsize
# Total size in bytes for entire array
self.verticesDataLength = self.verticesLength * self.verticesItemSize
# Number of vertices in the array
self.numberOfVertices = int(self.verticesLength / 3)
# Tell gl to prepare a buffer
self.vertexBuffer = self.gl.glGenBuffers(1)
# Say that the buffer is of type GL_ARRAY_BUFFER
self.gl.glBindBuffer(self.gl.GL_ARRAY_BUFFER, self.vertexBuffer)
# Copy data into the buffer
self.gl.glBufferData(self.gl.GL_ARRAY_BUFFER, self.verticesDataLength,
self.vertices.tobytes(), self.gl.GL_STATIC_DRAW)
# Say that the somePosition attribute should be read from the current array, that it should take three values at a
# time (x, y, z), and that they are of the type GL_FLOAT
self.gl.glVertexAttribPointer(self.somePosition, 3, self.gl.GL_FLOAT,
False, 0, 0)
# When reading from the current data, start at position 0
self.gl.glEnableVertexAttribArray(0)
# Tell GL that whenever we run glClear, this is the color that
# should be used. We only need to do this once.
self.gl.glClearColor(0.1, 0.1, 0.1, 1.0)
self.dumpGLLogMessages("setupGL()")
def paintGL(self):
self.gl.glClear(self.gl.GL_COLOR_BUFFER_BIT
| self.gl.GL_DEPTH_BUFFER_BIT)
# Draw points, starting at vertex number, number of vertices to draw. Since we enabled attribarrays, it will
# fetch data from the array buffer
self.gl.glDrawArrays(self.gl.GL_POINTS, 0, self.numberOfVertices)
self.dumpGLLogMessages("paintGL()")
def resizeGL(self, width, height):
pass
class TestCanvas(Canvas):
def __init__(self):
with open("vertex.glsl", "r") as f:
self.vertexShaderSource = f.read()
with open("fragment.glsl", "r") as f:
self.fragmentShaderSource = f.read()
if self.vertexShaderSource is None:
raise Exception("Could not load the source for the vertex shader")
if self.fragmentShaderSource is None:
raise Exception(
"Could not load the source for the fragment shader")
# Use an initial scale assuming width = height (should always be overwritten
# in the resizeGL method below)
self.currentScaling = QVector4D(1.0, 1.0, 1.0, 1.0)
super(TestCanvas, self).__init__()
# Use a non-square initial size
def sizeHint(self):
info("TESTCANVAS", "using overridden sizeHint()")
return QSize(600, 600)
def setupGL(self):
self.program = QOpenGLShaderProgram(self.context())
info("PROGRAM", self.program)
# addShaderFromSourceCode() only returns a bool telling whether everything went well
if self.program.addShaderFromSourceCode(QOpenGLShader.Vertex,
self.vertexShaderSource):
info("VERTEX SHADER",
"Managed to load and parse the vertex shader")
if self.program.addShaderFromSourceCode(QOpenGLShader.Fragment,
self.fragmentShaderSource):
info("FRAGMENT SHADER",
"Managed to load and parse the fragment shader")
# Compile and bind the shader program to the current context
self.program.link()
self.program.bind()
# Bind the shader attribute for transfering vertex positions to a python variable
self.somePosition = self.gl.glGetAttribLocation(
self.program.programId(), "somePosition")
# Bind the shader attribute for transfering vertex colors to a python variable
self.inputColor = self.gl.glGetAttribLocation(self.program.programId(),
"inputColor")
# Bind the shader "uniform" for controling the viewport scale of the vertex positions
self.viewportScaling = self.gl.glGetUniformLocation(
self.program.programId(), "viewportScaling")
# Bind the shader "uniform" for controling the rotation of the object
self.objectRotation = self.gl.glGetUniformLocation(
self.program.programId(), "objectRotation")
# Here we mix vertex data (x, y, z) with color data (r, g, b, a).
self.vertices = array.array(
'f',
[
-0.5,
-0.5,
0.0,
1.0,
0.0,
0.0,
1.0, # Bottom left is red
-0.5,
0.5,
0.0,
0.0,
1.0,
0.0,
1.0, # Top left is green
0.5,
0.5,
0.0,
0.0,
0.0,
1.0,
1.0, # Top right is blue
0.5,
-0.5,
0.0,
1.0,
1.0,
0.0,
1.0 # Bottom right is yellow
])
# Buffer info returns a tuple where the second part is number of elements in the array
self.verticesLength = self.vertices.buffer_info()[1]
# Each vertex is specified with with seven values (xyzrgba)
self.arrayCellsPerVertex = 7
# Size in bytes for each vertex specification (self.vertices.itemsize is the size in bytes
# of a single array cell)
self.vertexSpecificationSize = self.vertices.itemsize * self.arrayCellsPerVertex
# In bytes, where in a vertex specification does the color data start? (it starts after
# x, y, z.. i.e after 3 array cells)
self.colorBytesOffset = self.vertices.itemsize * 3
# Total size in bytes for entire array
self.verticesDataLength = self.verticesLength * self.vertices.itemsize
# Number of vertices in the array
self.numberOfVertices = int(self.verticesLength /
self.arrayCellsPerVertex)
# Tell gl to prepare a single buffer
self.vertexBuffer = self.gl.glGenBuffers(1)
# Say that the buffer is of type GL_ARRAY_BUFFER
self.gl.glBindBuffer(self.gl.GL_ARRAY_BUFFER, self.vertexBuffer)
# Copy data into the buffer
self.gl.glBufferData(self.gl.GL_ARRAY_BUFFER, self.verticesDataLength,
self.vertices.tobytes(), self.gl.GL_STATIC_DRAW)
# Say that the somePosition attribute should be read from the current array, that it should take three values at a
# time (x, y, z), and that they are of the type GL_FLOAT. We now also specify a byte offset (vertexSpecificationSize)
# to say that each new vertex specification is starting this many bytes after the prior one.
self.gl.glVertexAttribPointer(self.somePosition, 3, self.gl.GL_FLOAT,
False, self.vertexSpecificationSize, 0)
# Connect the array to the somePosition variable
self.gl.glEnableVertexAttribArray(self.somePosition)
# Say that the inputColor attribute should be read from the current array, that it should take four values at a
# time (r, g, b, a), and that they are of type GL_FLOAT. The same byte offset as for the position info is used, but
# we now also specify that the color information starts at colorBytesOffset bytes into each vertex specification
self.gl.glVertexAttribPointer(self.inputColor, 4, self.gl.GL_FLOAT,
False, self.vertexSpecificationSize,
self.colorBytesOffset)
# Connect the array to the inputColor variable
self.gl.glEnableVertexAttribArray(self.inputColor)
# Tell GL that whenever we run glClear, this is the color that
# should be used. We only need to do this once.
self.gl.glClearColor(0.1, 0.1, 0.1, 1.0)
self.dumpGLLogMessages("setupGL()")
def paintGL(self):
self.gl.glClear(self.gl.GL_COLOR_BUFFER_BIT
| self.gl.GL_DEPTH_BUFFER_BIT)
# Set rotation so that the quad is rotated 45 degrees clockwise
self.currentRotation = QVector3D(0.0, 0.0, 45.0)
self.program.setUniformValue(self.objectRotation, self.currentRotation)
# Before painting we set the scaling "uniform" parameter in the vertex shader.
# This will be used to scale the vertex positions.
self.program.setUniformValue(self.viewportScaling, self.currentScaling)
# Draw a quad starting at vertex number. Since we enabled attribarrays, it will fetch data from the array buffer
self.gl.glDrawArrays(self.gl.GL_QUADS, 0, self.numberOfVertices)
self.dumpGLLogMessages("paintGL()")
def resizeGL(self, width, height):
scaleX = 1.0
scaleY = 1.0
scaleZ = 1.0 # Will always be 1.0 since we don't scale depth
scaleW = 1.0 # A global scale factor, also always 1.0
if width > height:
scaleX = height / width
else:
scaleY = width / height
self.currentScaling = QVector4D(scaleX, scaleY, scaleZ, scaleW)
# Redraw since we changed the value of the scaling uniform
self.update()
class TestCanvas(Canvas):
def __init__(self):
with open("vertex.glsl", "r") as f:
self.vertexShaderSource = f.read()
with open("fragment.glsl", "r") as f:
self.fragmentShaderSource = f.read()
if self.vertexShaderSource is None:
raise Exception("Could not load the source for the vertex shader")
if self.fragmentShaderSource is None:
raise Exception(
"Could not load the source for the fragment shader")
super(TestCanvas, self).__init__()
def setupGL(self):
self.program = QOpenGLShaderProgram(self.context())
info("PROGRAM", self.program)
# addShaderFromSourceCode() only returns a bool telling whether everything went well
if self.program.addShaderFromSourceCode(QOpenGLShader.Vertex,
self.vertexShaderSource):
info("VERTEX SHADER",
"Managed to load and parse the vertex shader")
if self.program.addShaderFromSourceCode(QOpenGLShader.Fragment,
self.fragmentShaderSource):
info("FRAGMENT SHADER",
"Managed to load and parse the fragment shader")
# Compile and bind the shader program to the current context
self.program.link()
self.program.bind()
# Bind the shader attribute for transfering vertex positions to a python variable
self.somePosition = self.gl.glGetAttribLocation(
self.program.programId(), "somePosition")
# Bind the shader attribute for transfering vertex colors to a python variable
self.inputColor = self.gl.glGetAttribLocation(self.program.programId(),
"inputColor")
# Here we mix vertex data (x, y, z) with color data (r, g, b, a).
self.vertices = array.array(
'f',
[
-0.5,
-0.5,
0.0,
1.0,
0.0,
0.0,
1.0, # Bottom left is red
-0.5,
0.5,
0.0,
0.0,
1.0,
0.0,
1.0, # Top left is green
0.5,
0.5,
0.0,
0.0,
0.0,
1.0,
1.0, # Top right is blue
0.5,
-0.5,
0.0,
1.0,
1.0,
0.0,
1.0 # Bottom right is yellow
])
# Buffer info returns a tuple where the second part is number of elements in the array
self.verticesLength = self.vertices.buffer_info()[1]
# Each vertex is specified with with seven values (xyzrgba)
self.arrayCellsPerVertex = 7
# Size in bytes for each vertex specification (self.vertices.itemsize is the size in bytes
# of a single array cell)
self.vertexSpecificationSize = self.vertices.itemsize * self.arrayCellsPerVertex
# In bytes, where in a vertex specification does the color data start? (it starts after
# x, y, z.. i.e after 3 array cells)
self.colorBytesOffset = self.vertices.itemsize * 3
# Total size in bytes for entire array
self.verticesDataLength = self.verticesLength * self.vertices.itemsize
# Number of vertices in the array
self.numberOfVertices = int(self.verticesLength /
self.arrayCellsPerVertex)
# Tell gl to prepare a single buffer
self.vertexBuffer = self.gl.glGenBuffers(1)
# Say that the buffer is of type GL_ARRAY_BUFFER
self.gl.glBindBuffer(self.gl.GL_ARRAY_BUFFER, self.vertexBuffer)
# Copy data into the buffer
self.gl.glBufferData(self.gl.GL_ARRAY_BUFFER, self.verticesDataLength,
self.vertices.tobytes(), self.gl.GL_STATIC_DRAW)
# Say that the somePosition attribute should be read from the current array, that it should take three values at a
# time (x, y, z), and that they are of the type GL_FLOAT. We now also specify a byte offset (vertexSpecificationSize)
# to say that each new vertex specification is starting this many bytes after the prior one.
self.gl.glVertexAttribPointer(self.somePosition, 3, self.gl.GL_FLOAT,
False, self.vertexSpecificationSize, 0)
# Connect the array to the somePosition variable
self.gl.glEnableVertexAttribArray(self.somePosition)
# Say that the inputColor attribute should be read from the current array, that it should take four values at a
# time (r, g, b, a), and that they are of type GL_FLOAT. The same byte offset as for the position info is used, but
# we now also specify that the color information starts at colorBytesOffset bytes into each vertex specification
self.gl.glVertexAttribPointer(self.inputColor, 4, self.gl.GL_FLOAT,
False, self.vertexSpecificationSize,
self.colorBytesOffset)
# Connect the array to the inputColor variable
self.gl.glEnableVertexAttribArray(self.inputColor)
# Tell GL that whenever we run glClear, this is the color that
# should be used. We only need to do this once.
self.gl.glClearColor(0.1, 0.1, 0.1, 1.0)
self.dumpGLLogMessages("setupGL()")
def paintGL(self):
self.gl.glClear(self.gl.GL_COLOR_BUFFER_BIT
| self.gl.GL_DEPTH_BUFFER_BIT)
# Draw a quad starting at vertex number. Since we enabled attribarrays, it will fetch data from the array buffer
self.gl.glDrawArrays(self.gl.GL_QUADS, 0, self.numberOfVertices)
self.dumpGLLogMessages("paintGL()")
def resizeGL(self, width, height):
pass
