pyside.opengles.py

pyside.opengles.py

# -*- coding: utf-8 -*-
#!/usr/bin/python
 
import sys

from PySide.QtCore import *
from PySide.QtGui import *
from PySide.QtOpenGL import *

from simple_gles_wrapper import GL # https://gist.github.com/d3b869dd3fbc428728d2

vertex_shader_source = """
  
  attribute highp vec4 vertex;
  uniform mediump mat4 matrix;
  
  void main(void){
    gl_Position = matrix * vertex;
  }
  
"""

fragment_shader_source = """

  uniform mediump vec4 color;
  
  void main(void){
    gl_FragColor = color;
  }

"""


class MyGLWidget(QGLWidget):
  
  def __init__(self, parent=None):
    QGLWidget.__init__(self, parent)
    self.vertices = [
      QVector4D(0.5,0.0,0.0,1.0),
      QVector4D(0.0,0.5,0.0,1.0),
      QVector4D(0.5,0.5,0.0,1.0),
      QVector4D(0.5,0.0,0.0,1.0),
      QVector4D(0.5,0.5,0.0,1.0),
      QVector4D(0.0,0.5,0.0,1.0)
    ]
    self.matrix = QMatrix4x4(
      1.0, 0.0, 0.0, 0.0,
      0.0, 1.0, 0.0, 0.0,
      0.0, 0.0, 1.0, 0.0,
      0.0, 0.0, 0.0, 1.0
    )
    self.color = QColor(0, 255, 0, 255)
  
  def initializeGL(self):
    
    GL.glEnable(GL.GL_DEPTH_TEST)
    GL.glEnable(GL.GL_CULL_FACE)
    
    self.program = QGLShaderProgram(self.context())
    
    # vertex shader
    self.vertex_shader = QGLShader(QGLShader.Vertex)
    self.vertex_shader.compileSourceCode(vertex_shader_source)
    self.program.addShader(self.vertex_shader)
    
    # frag shader
    self.fragment_shader = QGLShader(QGLShader.Fragment)
    self.fragment_shader.compileSourceCode(fragment_shader_source)
    self.program.addShader(self.fragment_shader)
    
    self.program.link()
    
    
  def resizeGL(self, width, height):
    side = min(width, height)
    GL.glViewport((width - side) / 2, (height - side) / 2, side, side)

  def paintGL(self):
    
    # bind shader program
    self.program.bind()
    
    # set vertices for shader program
    vertexLocation = self.program.attributeLocation("vertex")
    self.program.setAttributeArray(vertexLocation, self.vertices)
    
    # set matrix for shader program
    matrixLocation = self.program.uniformLocation("matrix")
    self.program.setUniformValue(matrixLocation, self.matrix)
    
    # set color for shader program
    colorLocation = self.program.uniformLocation("color")
    self.program.setUniformValue(colorLocation, self.color)
    
    # draw    
    self.program.enableAttributeArray(vertexLocation)
    GL.glDrawArrays(GL.GL_TRIANGLE_FAN, 0, 6)
    self.program.disableAttributeArray(vertexLocation)
    
    # unbind shader
    self.program.release()
    




if __name__ == '__main__':
    app = QApplication(sys.argv)
    window = MyGLWidget()
    window.show()
    sys.exit(app.exec_())