GLSL Classes

GLSL is not object oriented, there are no classes or method calls. GLSL4.0 has subroutine variables that can provide an object oriented solution, but this is not compatible with GLSL in WebGL.

PythonJS GPU Class

In the example below an array of MyObject is created and uploaded to the GPU, where it is iterated over. The method call s.mymethod(1.1, 2.2) translates to MyObject_mymethod(s, 1.1, 2.2) in the GLSL shader.

@gpu.object
class MyObject:
 @gpu.method
 float def subroutine(self, x,y):
  float x
  float y
  return x + y * self.attr2

 @gpu.method
 float def mymethod(self, x,y):
  float x
  float y
  if self.index == 0:
   return -20.5
  elif self.index == 0:
   return 0.6
  else:
   return self.subroutine(x,y) * self.attr1

 def __init__(self, a, b, i):
  self.attr1 = a
  self.attr2 = b
  self.index = int16(i)


class myclass:
 def run(self, w):
  self.array = [MyObject(1.1,1.2,x) for x in range(w)]

  @returns( array=64 )
  @gpu.main
  def gpufunc():
   struct* A = self.array
   float b = 0.0

   for s in iter(A):
    b += s.mymethod(1.1, 2.2)

   return b

  return gpufunc()