Source Code for Module toon.effects.lumakey

  1  #!/usr/bin/env python 
  2  """ 
  3  GLSL shaders with SDL, OpenGL texture and Python 
  4   
  5  To test with glslang-run :  
  6  ./scripts/glslang-run -f lumakey -d 1 
  7  telnet localhost 15555 
  8  b 0,0,0 
  9  x invert 1 
 10  x alpha_over 0 
 11  x alpha_under 1 
 12  """ 
 13  from pygame.locals import * 
 14  from OpenGL.GL import * 
 15  from OpenGL.error import GLError 
 16  from OpenGL.GLU import * 
 17  from rats.glsl import ShaderProgram 
 18  from rats.glsl import ShaderError 
 19  from toon import fx 
 20  from toon import optgroup 
 21   
 22 -class LumaKeyOptions(optgroup.OptionsGroup): 
 23 -    def __init__(self): 
 24          self.avgluma = [1.0, 1.0, 1.0] 
 25          self.luma_gate = 0.3 
 26          self.saturation = 1.0 
 27          self.contrast = 1.0 
 28          self.invert = 1 # 0 or 1 
 29          self.brightness = 1.0 
 30          self.alpha_under = 1.0 
 31          self.alpha_over = 0.0 
 32          self.texture_id = 0 
 33   
 34  # ---------------------------- glsl vertex shader ---------- 
 35  vert = """ 
 36  /** 
 37   * Vertex shader that does nothing 
 38   */ 
 39  // variables passed to the fragment shader 
 40  varying vec2 texcoord0; 
 41  varying vec2 texdim0; 
 42   
 43  void main() 
 44  { 
 45      gl_Position = ftransform(); 
 46      texcoord0 = vec2(gl_TextureMatrix[0] * gl_MultiTexCoord0); 
 47      texdim0 = vec2(abs(gl_TextureMatrix[0][0][0]), abs(gl_TextureMatrix[0][1][1])); 
 48  } 
 49  """ 
 50   
 51  # ---------------------------- glsl fragment shader ---------- 
 52  frag = """ 
 53  #extension GL_ARB_texture_rectangle : enable 
 54  /** 
 55   * Binary luma keying. 
 56   *  
 57   * :author: Alexandre Quessy <alexandre@quessy.net> 2009 
 58   * :license: GNU Public License version 3 
 59   */ 
 60   
 61  //// user-configurable variables (read-only) 
 62  uniform float luma_gate; // [0., 1.] 
 63  uniform vec3 avgluma; 
 64  uniform float saturation; 
 65  uniform float contrast; 
 66  uniform int invert; 
 67  uniform float brightness; 
 68  uniform float alpha_under; 
 69  uniform float alpha_over; 
 70   
 71  // the texture 
 72  uniform sampler2DRect image; 
 73   
 74  // constants 
 75  const vec3 LumCoeff = vec3(0.2125, 0.7154, 0.0721); 
 76  const vec3 unity = vec3(1.0, 1.0, 1.0); 
 77  // data passed from vertex shader: 
 78  varying vec2 texcoord0; 
 79  varying vec2 texdim0; 
 80   
 81  void main(void) 
 82  { 
 83      // begin applying brcosa 
 84      vec3 input_color = texture2DRect(image, texcoord0).rgb; 
 85          vec3 intensity = vec3(dot(input_color, LumCoeff)); 
 86          vec3 color = mix(intensity, input_color, saturation); 
 87      float alpha = alpha_under; 
 88      // check if close to target luminosity 
 89      float input_alpha = gl_Color.a; 
 90      if (intensity[0] >= luma_gate) 
 91      { 
 92          alpha = alpha_over; 
 93      } 
 94      // finish applying brcosa 
 95          color = mix(avgluma, color, contrast); 
 96      if (invert == 1)  
 97      { 
 98          color = unity - color; 
 99      } 
100          color *= brightness; 
101          gl_FragColor = vec4(color, alpha * input_alpha); 
102  } 
103  """ 
104   
105 -class LumaKeyEffect(fx.Effect): 
106      """ 
107      Makes all the image desaturated expect target color. 
108      """ 
109 -    def __init__(self): 
110          fx.Effect.__init__(self) 
111          self.program = None 
112          self.options = LumaKeyOptions() 
113          self.name = "lumakey" 
114          #print("init %s" % (self.name)) 
115           
116 -    def setup(self): 
117          global vert 
118          global frag 
119          if True: 
120          #try: 
121              self.program = ShaderProgram() 
122              self.program.add_shader_text(GL_VERTEX_SHADER_ARB, vert) 
123              self.program.add_shader_text(GL_FRAGMENT_SHADER_ARB, frag) 
124              self.program.linkShaders() 
125          #except Exception, e:  
126          #    print(e.message) 
127          #else: 
128              self.loaded = True 
129              #print("Set up effect %s" % (self.name)) 
130              #print(self.config) 
131       
132 -    def pre_draw(self): 
133          if self.enabled and self.loaded: 
134              try: 
135                  self.program.enable() 
136              except Exception, e:  
137                  print(e.message) 
138              self.program.glUniform1i("image", self.options.texture_id) 
139              self.program.glUniform1f("luma_gate", self.options.luma_gate) 
140              self.program.glUniform3f("avgluma", *self.options.avgluma) 
141              self.program.glUniform1f("alpha_over", self.options.alpha_over) 
142              self.program.glUniform1f("alpha_under", self.options.alpha_under) 
143              self.program.glUniform1f("saturation", self.options.saturation) 
144              self.program.glUniform1f("contrast", self.options.contrast) 
145              self.program.glUniform1f("brightness", self.options.brightness) 
146              self.program.glUniform1i("invert", self.options.invert) 
147   
148 -    def post_draw(self): 
149          if self.enabled and self.loaded: 
150              try: 
151                  self.program.disable() 
152              except Exception, e:  
153                  print e.message 
154   
155 -def create_effect(): 
156      return LumaKeyEffect() 
157