109 lines
3.4 KiB
Python
109 lines
3.4 KiB
Python
from OpenGL.GL import *
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from OpenGL.GL import shaders
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## For centralizing and managing vertex/fragment shader programs.
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def initShaders():
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global Shaders
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Shaders = [
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ShaderProgram('balloon', [ ## increases fragment alpha as the normal turns orthogonal to the view
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VertexShader("""
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varying vec3 normal;
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void main() {
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normal = normalize(gl_NormalMatrix * gl_Normal);
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//vec4 color = normal;
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//normal.w = min(color.w + 2.0 * color.w * pow(normal.x*normal.x + normal.y*normal.y, 2.0), 1.0);
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gl_FrontColor = gl_Color;
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gl_BackColor = gl_Color;
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gl_Position = ftransform();
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}
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"""),
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FragmentShader("""
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varying vec3 normal;
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void main() {
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vec4 color = gl_Color;
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color.w = min(color.w + 2.0 * color.w * pow(normal.x*normal.x + normal.y*normal.y, 5.0), 1.0);
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gl_FragColor = color;
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}
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""")
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]),
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ShaderProgram('point_sprite', [ ## allows specifying point size using normal.x
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## See:
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##
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## http://stackoverflow.com/questions/9609423/applying-part-of-a-texture-sprite-sheet-texture-map-to-a-point-sprite-in-ios
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## http://stackoverflow.com/questions/3497068/textured-points-in-opengl-es-2-0
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##
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##
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VertexShader("""
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void main() {
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gl_FrontColor=gl_Color;
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gl_PointSize = gl_Normal.x;
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gl_Position = ftransform();
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}
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"""),
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#FragmentShader("""
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##version 120
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#uniform sampler2D texture;
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#void main ( )
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#{
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#gl_FragColor = texture2D(texture, gl_PointCoord) * gl_Color;
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#}
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#""")
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]),
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]
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CompiledShaderPrograms = {}
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def getShaderProgram(name):
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return ShaderProgram.names[name]
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class VertexShader:
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def __init__(self, code):
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self.code = code
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self.compiled = None
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def shader(self):
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if self.compiled is None:
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self.compiled = shaders.compileShader(self.code, GL_VERTEX_SHADER)
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return self.compiled
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class FragmentShader:
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def __init__(self, code):
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self.code = code
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self.compiled = None
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def shader(self):
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if self.compiled is None:
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self.compiled = shaders.compileShader(self.code, GL_FRAGMENT_SHADER)
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return self.compiled
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class ShaderProgram:
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names = {}
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def __init__(self, name, shaders):
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self.name = name
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ShaderProgram.names[name] = self
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self.shaders = shaders
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self.prog = None
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def program(self):
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if self.prog is None:
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compiled = [s.shader() for s in self.shaders] ## compile all shaders
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self.prog = shaders.compileProgram(*compiled) ## compile program
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return self.prog
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def __enter__(self):
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glUseProgram(self.program())
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def __exit__(self, *args):
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glUseProgram(0)
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def uniform(self, name):
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"""Return the location integer for a uniform variable in this program"""
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return glGetUniformLocation(self.program(), name)
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initShaders() |