code: def __enter__(self):
      ## Program should have a uniform block declared:
      ##
      ## layout (std140) uniform blockName {
      ##     vec4 diffuse;
      ##     vec4 ambient;
      ## };
  
      ## pick any-old binding point. (there are a limited number of these per-program
      bindPoint = 1
  
      ## get the block index for a uniform variable in the shader
      blockIndex = glGetUniformBlockIndex(self.program(), "blockName")
  
      ## give the shader block a binding point
      glUniformBlockBinding(self.program(), blockIndex, bindPoint)
  
      ## create a buffer
      buf = glGenBuffers(1)
      glBindBuffer(GL_UNIFORM_BUFFER, buf)
      glBufferData(GL_UNIFORM_BUFFER, size, data, GL_DYNAMIC_DRAW)
      ## also possible to use glBufferSubData to fill parts of the buffer
  
      ## bind buffer to the same binding point
      glBindBufferBase(GL_UNIFORM_BUFFER, bindPoint, buf)
  
imports: from OpenGL.GL import *
  from OpenGL.GL import shaders
  import numpy
  import re
label_desc: Use image node_id 1 for calling the HeightColorShader obj's underlying member method code with example usage: obj.__enter__() without return types