# $Id$

class KX_PolygonMaterial:
	"""
	This is the interface to materials in the game engine.
	
	Materials define the render state to be applied to mesh objects.
	
	Warning:  Some of the methods/variables are CObjects.  If you mix these up,
	you will crash blender.
	
	This example requires:
		- PyOpenGL http://pyopengl.sourceforge.net/
		- GLEWPy http://glewpy.sourceforge.net/
	Example::
		
		import GameLogic
		import OpenGL
		from OpenGL.GL import *
		from OpenGL.GLU import *
		import glew
		from glew import *
		
		glewInit()
		
		vertex_shader = \"\"\"
		
		void main(void)
		{
			gl_Position = ftransform();
		}
		\"\"\"
		
		fragment_shader =\"\"\"
		
		void main(void)
		{
			gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
		}
		\"\"\"
		
		class MyMaterial:
			def __init__(self):
				self.pass_no = 0
				# Create a shader
				self.m_program = glCreateProgramObjectARB()
				# Compile the vertex shader
				self.shader(GL_VERTEX_SHADER_ARB, (vertex_shader))
				# Compile the fragment shader
				self.shader(GL_FRAGMENT_SHADER_ARB, (fragment_shader))
				# Link the shaders together
				self.link()
				
			def PrintInfoLog(self, tag, object):
				\"\"\"
				PrintInfoLog prints the GLSL compiler log
				\"\"\"
				print "Tag: 	def PrintGLError(self, tag = ""):
				
			def PrintGLError(self, tag = ""):
				\"\"\"
				Prints the current GL error status
				\"\"\"
				if len(tag):
					print tag
				err = glGetError()
				if err != GL_NO_ERROR:
					print "GL Error: %s\\n"%(gluErrorString(err))
		
			def shader(self, type, shaders):
				\"\"\"
				shader compiles a GLSL shader and attaches it to the current
				program.
				
				type should be either GL_VERTEX_SHADER_ARB or GL_FRAGMENT_SHADER_ARB
				shaders should be a sequence of shader source to compile.
				\"\"\"
				# Create a shader object
				shader_object = glCreateShaderObjectARB(type)
		
				# Add the source code
				glShaderSourceARB(shader_object, len(shaders), shaders)
				
				# Compile the shader
				glCompileShaderARB(shader_object)
				
				# Print the compiler log
				self.PrintInfoLog("vertex shader", shader_object)
				
				# Check if compiled, and attach if it did
				compiled = glGetObjectParameterivARB(shader_object, GL_OBJECT_COMPILE_STATUS_ARB)
				if compiled:
					glAttachObjectARB(self.m_program, shader_object)
					
				# Delete the object (glAttachObjectARB makes a copy)
				glDeleteObjectARB(shader_object)
				
				# print the gl error log
				self.PrintGLError()
				
			def link(self):
				\"\"\"
				Links the shaders together.
				\"\"\"
				# clear error indicator		
				glGetError()
				
				glLinkProgramARB(self.m_program)
		
				self.PrintInfoLog("link", self.m_program)
			
				linked = glGetObjectParameterivARB(self.m_program, GL_OBJECT_LINK_STATUS_ARB)
				if not linked:
					print "Shader failed to link"
					return
		
				glValidateProgramARB(self.m_program)
				valid = glGetObjectParameterivARB(self.m_program, GL_OBJECT_VALIDATE_STATUS_ARB)
				if not valid:
					print "Shader failed to validate"
					return
				
			def activate(self, rasty, cachingInfo, mat):
				self.pass_no+=1
				if (self.pass_no == 1):
					glDisable(GL_COLOR_MATERIAL)
					glUseProgramObjectARB(self.m_program)
					return True
				
				glEnable(GL_COLOR_MATERIAL)
				glUseProgramObjectARB(0)
				self.pass_no = 0	
				return False
		
		obj = GameLogic.getCurrentController().getOwner()
		
		mesh = obj.getMesh(0)
		
		for mat in mesh.materials:
			mat.setCustomMaterial(MyMaterial())
			print mat.texture
	
	@ivar texture: Texture name
	@type texture: string (read only)
	
	@ivar gl_texture: OpenGL texture handle (eg for glBindTexture(GL_TEXTURE_2D, gl_texture)
	@type gl_texture: integer (read only)
	
	@ivar material: Material name
	@type material: string (read only)
	
	@ivar tface: Texture face properties
	@type tface: CObject (read only)
	
	@ivar tile: Texture is tiling
	@type tile: boolean
	@ivar tilexrep: Number of tile repetitions in x direction.
	@type tilexrep: integer
	@ivar tileyrep: Number of tile repetitions in y direction.
	@type tileyrep: integer
	
	@ivar drawingmode: Drawing mode for the material.
		- 2  (drawingmode & 4)     Textured
		- 4  (drawingmode & 16)    Light
		- 14 (drawingmode & 16384) 3d Polygon Text
	@type drawingmode: bitfield
	
	@ivar transparent: This material is transparent.  All meshes with this
		material will be rendered after non transparent meshes from back
		to front.
	@type transparent: boolean
	
	@ivar zsort: Transparent polygons in meshes with this material will be sorted back to
		front before rendering.
		Non-Transparent polygons will be sorted front to back before rendering.
	@type zsort: boolean
	
	@ivar lightlayer: Light layers this material affects.
	@type lightlayer: bitfield.
	
	@ivar triangle: Mesh data with this material is triangles.  It's probably not safe to change this.
	@type triangle: boolean
	
	@ivar diffuse: The diffuse colour of the material.  black = [0.0, 0.0, 0.0] white = [1.0, 1.0, 1.0]
	@type diffuse: list [r, g, b]
	@ivar specular: The specular colour of the material. black = [0.0, 0.0, 0.0] white = [1.0, 1.0, 1.0]
	@type specular: list [r, g, b] 
	@ivar shininess: The shininess (specular exponent) of the material. 0.0 <= shininess <= 128.0
	@type shininess: float
	@ivar specularity: The amount of specular of the material. 0.0 <= specularity <= 1.0
	@type specularity: float
	"""
	def updateTexture(tface, rasty):
		"""
		Updates a realtime animation.
		
		@param tface: Texture face (eg mat.tface)
		@type tface: CObject
		@param rasty: Rasterizer
		@type rasty: CObject
		"""
	def setTexture(tface):
		"""
		Sets texture render state.
		
		Example::
			mat.setTexture(mat.tface)
		
		@param tface: Texture face
		@type tface: CObject
		"""
	def activate(rasty, cachingInfo):
		"""
		Sets material parameters for this object for rendering.
		
		Material Parameters set:
			1. Texture
			2. Backface culling
			3. Line drawing
			4. Specular Colour
			5. Shininess
			6. Diffuse Colour
			7. Polygon Offset.
		
		@param rasty: Rasterizer instance.
		@type rasty: CObject
		@param cachingInfo: Material cache instance.
		@type cachingInfo: CObject
		"""
	def setCustomMaterial(material):
		"""
		Sets the material state setup object.
		
		Using this method, you can extend or completely replace the gameengine material
		to do your own advanced multipass effects.
		
		Use this method to register your material class.  Instead of the normal material,
		your class's activate method will be called just before rendering the mesh.  
		This should setup the texture, material, and any other state you would like.
		It should return True to render the mesh, or False if you are finished.  You should
		clean up any state Blender does not set before returning False.

		Activate Method Definition::
				def activate(self, rasty, cachingInfo, material):
			
		Example::
			class PyMaterial:
				def __init__(self):
					self.pass_no = -1
				
				def activate(self, rasty, cachingInfo, material):
					# Activate the material here.
					#
					# The activate method will be called until it returns False.
					# Every time the activate method returns True the mesh will
					# be rendered.
					#
					# rasty is a CObject for passing to material.updateTexture() 
					#       and material.activate()
					# cachingInfo is a CObject for passing to material.activate()
					# material is the KX_PolygonMaterial instance this material
					#          was added to
					
					# default material properties:
					self.pass_no += 1
					if self.pass_no == 0:
						material.activate(rasty, cachingInfo)
						# Return True to do this pass
						return True
					
					# clean up and return False to finish.
					self.pass_no = -1
					return False
			
			# Create a new Python Material and pass it to the renderer.
			mat.setCustomMaterial(PyMaterial())
		
		@param material: The material object.
		@type material: instance
		"""