//-
// ==========================================================================
// Copyright (C) 1995 - 2005 Alias Systems Corp. and/or its licensors.  All 
// rights reserved. 
// 
// The coded instructions, statements, computer programs, and/or related 
// material (collectively the "Data") in these files are provided by Alias 
// Systems Corp. ("Alias") and/or its licensors for the exclusive use of the 
// Customer (as defined in the Alias Software License Agreement that 
// accompanies this Alias software). Such Customer has the right to use, 
// modify, and incorporate the Data into other products and to distribute such 
// products for use by end-users.
//  
// THE DATA IS PROVIDED "AS IS".  ALIAS HEREBY DISCLAIMS ALL WARRANTIES 
// RELATING TO THE DATA, INCLUDING, WITHOUT LIMITATION, ANY AND ALL EXPRESS OR 
// IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND/OR FITNESS FOR A 
// PARTICULAR PURPOSE. IN NO EVENT SHALL ALIAS BE LIABLE FOR ANY DAMAGES 
// WHATSOEVER, WHETHER DIRECT, INDIRECT, SPECIAL, OR PUNITIVE, WHETHER IN AN 
// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, OR IN EQUITY, 
// ARISING OUT OF ACCESS TO, USE OF, OR RELIANCE UPON THE DATA.
// ==========================================================================
//+


///////////////////////////////////////////////////////////////////
//
// NOTE: PLEASE READ THE README.TXT FILE FOR INSTRUCTIONS ON
// COMPILING AND USAGE REQUIREMENTS.
//
// DESCRIPTION: NV20-specific (Geforce3) sample shader.
//				This shader is meant to allow cartoon-like effects.
//				It allows the user to specify a base decal texture,
//				and a lighting look-up texture.
//
//  This shader builds on the foundation demonstrated in the 
//  hwUnlitShader.
//
//
///////////////////////////////////////////////////////////////////


// Uncomment the #ifdef below if you want to debug the vertex program by
// output a COL0 value that corresponds to an intermediate calculation.
// The only sane way we could find to debug that thing.
//#define DEBUGGING_VERTEX_PROGRAM 1

#ifdef WIN32
#pragma warning( disable : 4786 )		// Disable STL warnings.
#endif

#include <maya/MIOStream.h>
#include <math.h>

#include <maya/MString.h>
#include <maya/MPlug.h>
#include <maya/MDagPath.h>
#include <maya/MDataBlock.h>
#include <maya/MDataHandle.h>
#include <maya/MArrayDataHandle.h>
#include <maya/MFnDependencyNode.h>
#include <maya/MFnNumericAttribute.h>
#include <maya/MFnTypedAttribute.h>
#include <maya/MFnLightDataAttribute.h>
#include <maya/MFloatVector.h>
#include <maya/MFnLight.h>
#include <maya/MFnStringData.h>
#include <maya/MFnPlugin.h>
#include <maya/MGlobal.h>
#include <maya/MSceneMessage.h>

#include <maya/MPoint.h>
#include <maya/MMatrix.h>
#include <maya/MVector.h>
#include <maya/MEulerRotation.h>
#include <maya/MFnNonAmbientLight.h>

// Include NVIDIA's helper libraries.  These libraries have
// copyright info in them so we cannot release them but we
// can use them to verify that the API works correctly.
//
#include <GL/gl.h>
#include <GL/glu.h>
#include <gl/glext.h>

#define GLH_EXT_SINGLE_FILE
#include "glh_extensions.h"
#undef GL_NV_vertex_array_range
#include "glh_genext.h"
#include "glh_obs.h"
using namespace glh;

#include "hwToonShader_NV20.h"
#include "ShadingConnection.h"

MTypeId hwToonShader_NV20::id( 0x00105443 );
/*static*/ const unsigned int hwToonShader_NV20::lookup_texture_size(256);


void hwToonShader_NV20::postConstructor( )
{
	setMPSafe(false);
}

// Static attribute instances.
//
MObject  hwToonShader_NV20::color;
MObject  hwToonShader_NV20::colorR;
MObject  hwToonShader_NV20::colorG;
MObject  hwToonShader_NV20::colorB;

MObject  hwToonShader_NV20::lightModel;
MObject  hwToonShader_NV20::lightModelR;
MObject  hwToonShader_NV20::lightModelG;
MObject  hwToonShader_NV20::lightModelB;

MObject  hwToonShader_NV20::camera;
MObject  hwToonShader_NV20::cameraX;
MObject  hwToonShader_NV20::cameraY;
MObject  hwToonShader_NV20::cameraZ;

MObject  hwToonShader_NV20::uCoord;
MObject  hwToonShader_NV20::vCoord;
MObject  hwToonShader_NV20::uvCoord;

MObject  hwToonShader_NV20::uBias;
MObject  hwToonShader_NV20::vBias;

MObject  hwToonShader_NV20::uvFilterSize;
MObject  hwToonShader_NV20::uvFilterSizeX;
MObject  hwToonShader_NV20::uvFilterSizeY;

MObject  hwToonShader_NV20::shininess;
MObject  hwToonShader_NV20::lightColor;
MObject  hwToonShader_NV20::lightColorR;
MObject  hwToonShader_NV20::lightColorG;
MObject  hwToonShader_NV20::lightColorB;

void hwToonShader_NV20::printGlError( const char *call )
{
    GLenum error;

	while( (error = glGetError()) != GL_NO_ERROR ) {
		assert(0);
	    cerr << call << ":" << error << " is " << (const char *)gluErrorString( error ) << "\n";
	}
}


// The Vertex Program for the textured-light-model shading effect.
// Meant to be used as a cartoon shader.
//
// CONSTANTS:
//  0- 3  4x4 ModelView-Projection composite matrix
//  4- 7  4x4 ModelView matrix
//  8-10  light amb/diff/spec
// 11     light dir vector (from surface to light, in object space)
// 12	  camera position in object space (possibly not normalized)

// VERTEX REGISTERS (mapped so that standard gl calls work):
// 0 - coord
// 2 - normal
// 3 - primary color
// 8 - texcoord0 (lighting look-up table)
// 9 - texcoord1 (decal, optional)

// REGISTERS:
//
// R0 - normalized view (surface-to-camera) direction in object space.
// R1 - normalized surface normal in object space.
// R2 - normalized light (surface-to-light) direction.
//
//
char vertexProgramString[] = 
	"!!VP1.0\n"

		// Multiply the vertex coords by the modelview-projection composite matrix,
		// to get clip space coordinates.
		"DP4   o[HPOS].x, c[0], v[0];"
		"DP4   o[HPOS].y, c[1], v[0];"
		"DP4   o[HPOS].z, c[2], v[0];"
		"DP4   o[HPOS].w, c[3], v[0];"

		// Normalize the N (normal), in case the modelview matrix is not a simple rotation.
		"MOV   R1, v[2];"
		"DP3   R1.w, R1, R1;"			
		"RSQ   R1.w, R1.w;"
		"MUL   R1.xyz, R1, R1.w;"

		// Normalize the L (light) direction.
		"MOV   R2, c[11];"
		"DP3   R2.w, R2, R2;"			
		"RSQ   R2.w, R2.w;"
		"MUL   R2.xyz, R2, R2.w;"

		// The vertex position, normal and light positions are expressed in object space at
		// this point. We need to find the view direction in object space too.
		"ADD   R0, c[12], -v[0];"		// view direction, from surface to camera.
		"DP3   R0.w, R0, R0;"			// normalize the view direction.
		"RSQ   R0.w, R0.w;"
		"MUL   R0.xyz, R0, R0.w;"
		
		// Find the texture coordinates to fetch from the toon-param texture.
		// u = N dot L.
		// v = N dot V.
		"DP3 o[TEX0].x, R1, R2;"
		"DP3 o[TEX0].y, R1, R0;"

		// Move the texture coordinates from tex 1 if appropriate.
		"MOV o[TEX1], v[9];"

#ifndef DEBUGGING_VERTEX_PROGRAM
		// Put diffuse lighting into color.
		"MUL o[COL0], v[3], c[9];"
#else
		// VISUALIZE VECTOR
		"MOV o[COL0], R2;"	// normalized light
#endif		

        "END";


char vertexProgramStringPoint[] = 
	"!!VP1.0\n"

		// Multiply the vertex coords by the modelview-projection composite matrix,
		// to get clip space coordinates.
		"DP4   o[HPOS].x, c[0], v[0];"
		"DP4   o[HPOS].y, c[1], v[0];"
		"DP4   o[HPOS].z, c[2], v[0];"
		"DP4   o[HPOS].w, c[3], v[0];"

		// Normalize the N (normal), in case the modelview matrix is not a simple rotation.
		"MOV   R1, v[2];"
		"DP3   R1.w, R1, R1;"			
		"RSQ   R1.w, R1.w;"
		"MUL   R1.xyz, R1, R1.w;"

		// Compute normalize the L (light) direction.
		"ADD   R2, c[11], -v[0];"
		"DP3   R2.w, R2, R2;"			
		"RSQ   R2.w, R2.w;"
		"MUL   R2.xyz, R2, R2.w;"

		// The vertex position, normal and light positions are expressed in object space at
		// this point. We need to find the view direction in object space too.
		"ADD   R0, c[12], -v[0];"		// view direction, from surface to camera.
		"DP3   R0.w, R0, R0;"			// normalize the view direction.
		"RSQ   R0.w, R0.w;"
		"MUL   R0.xyz, R0, R0.w;"
		
		// Find the texture coordinates to fetch from the toon-param texture.
		// u = N dot L.
		// v = N dot V.
		"DP3 o[TEX0].x, R1, R2;"
		"DP3 o[TEX0].y, R1, R0;"

		// Move the texture coordinates from tex 1 if appropriate.
		"MOV o[TEX1], v[9];"

#ifndef DEBUGGING_VERTEX_PROGRAM
		// Put diffuse lighting into color.
		"MUL o[COL0], v[3], c[9];"
//		"MOV o[COL0], c[9];"
#else
		// VISUALIZE VECTOR
		"MOV o[COL0], R2;"	// normalized light
#endif		

        "END";


char vertexProgramStringPointDecay[] = 
	"!!VP1.0\n"

		// Multiply the vertex coords by the modelview-projection composite matrix,
		// to get clip space coordinates.
		"DP4   o[HPOS].x, c[0], v[0];"
		"DP4   o[HPOS].y, c[1], v[0];"
		"DP4   o[HPOS].z, c[2], v[0];"
		"DP4   o[HPOS].w, c[3], v[0];"

		// Normalize the N (normal), in case the modelview matrix is not a simple rotation.
		"MOV   R1, v[2];"
		"DP3   R1.w, R1, R1;"			
		"RSQ   R1.w, R1.w;"
		"MUL   R1.xyz, R1, R1.w;"

		// Compute normalize the L (light) direction.
		"ADD   R2, c[11], -v[0];"
		"DP3   R2.w, R2, R2;"			
		"RSQ   R2.w, R2.w;"
		"MUL   R2.xyz, R2, R2.w;"

		// The vertex position, normal and light positions are expressed in object space at
		// this point. We need to find the view direction in object space too.
		"ADD   R0, c[12], -v[0];"		// view direction, from surface to camera.
		"DP3   R0.w, R0, R0;"			// normalize the view direction.
		"RSQ   R0.w, R0.w;"
		"MUL   R0.xyz, R0, R0.w;"
		
		// Find the texture coordinates to fetch from the toon-param texture.
		// u = N dot L.
		// v = N dot V.
		"DP3 o[TEX0].x, R1, R2;"
		"DP3 o[TEX0].y, R1, R0;"

		// Move the texture coordinates from tex 1 if appropriate.
		"MOV o[TEX1], v[9];"

#ifndef DEBUGGING_VERTEX_PROGRAM
		// Multiply diffuse lighting into material color.
		// Take into account decay
		"MOV R4, c[9];"
		"MOV R5, c[9];"
		"MUL R5.xyz, R4, R2.w;"
		"MUL o[COL0], v[3], R5;"
#else
		// VISUALIZE VECTOR
		"MOV o[COL0], R2;"	// normalized light
#endif		

        "END";


void initVertexProgram(const char vertexProgramCode[], GLuint* pVertexProgramId)
{
	// Allocate and initialize the vertex program.
	glGenProgramsNV(1, pVertexProgramId);
	GLenum error = glGetError();
	assert(error == GL_NO_ERROR);

	// Load the program.
	unsigned int length = strlen(vertexProgramCode);
	glLoadProgramNV(GL_VERTEX_PROGRAM_NV, *pVertexProgramId, length, 
		(const GLubyte *) vertexProgramCode);
	error = glGetError();

	// If an error occured, find the location in the vertex program
	// code and assert.
	if (error != GL_NO_ERROR)
	{
		// If an error occured, it's most likely due to a syntax or 
		// logic error in the vertex program. The error position
		// below will contain the index in the vertex program
		// string that is faulty. See the NV_vertex_program
		// extension specification for more details.
		if (error == GL_INVALID_OPERATION)
		{
			int error_position = -2;

			glGetIntegerv(GL_PROGRAM_ERROR_POSITION_NV, &error_position);

			// Most likely a bug in the vertex program code...
			assert(0);
		}
	}
}

// Load the vertexProgram and fill in the necessary constants used in the vertex program.
//
void hwToonShader_NV20::loadVertexProgramGL()
{
	GLenum error = glGetError();
	assert(!error);

	// If the vertex programs haven't been loaded yet,
	// do it now. (Note that they are shared between all contexts.)
	if (!fVertexProgramsLoaded)
	{
		initVertexProgram(vertexProgramString, &fVertexProgramDirectional);
		initVertexProgram(vertexProgramStringPointDecay, &fVertexProgramPointDecay);
		initVertexProgram(vertexProgramStringPoint, &fVertexProgramPointNoDecay);
		fVertexProgramsLoaded = true;
	}

	// Set up the constant values.
	//
	// CONSTANTS:
	//  0- 3  4x4 ModelView-Projection composite matrix
	//  4- 7  4x4 ModelView  matrix
	//  8-10  light amb/diff/spec
	// 11     light dir vector (from surface to light)
	//
	glTrackMatrixNV(GL_VERTEX_PROGRAM_NV, 0, GL_MODELVIEW_PROJECTION_NV, GL_IDENTITY_NV);
	glTrackMatrixNV(GL_VERTEX_PROGRAM_NV, 4, GL_MODELVIEW, GL_IDENTITY_NV);
	glProgramParameter4fNV(GL_VERTEX_PROGRAM_NV, 8, 1, 1, 1, 1);
	glProgramParameter4fNV(GL_VERTEX_PROGRAM_NV, 9, 1, 1, 1, 1);
	glProgramParameter4fNV(GL_VERTEX_PROGRAM_NV, 10, 1, 1, 1, 1);
	glProgramParameter4fNV(GL_VERTEX_PROGRAM_NV, 11, -lightRotation[0], -lightRotation[1], -lightRotation[2], 0);	// light dir...
}

void hwToonShader_NV20::bind_lookup_table()
{
//	make_lookup_texture();

	lookup_texture->bind();

	if (fLookupTextureReprocessed)
	{
		glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE_ALPHA, lookup_texture_size, lookup_texture_size, 0, GL_LUMINANCE_ALPHA, GL_UNSIGNED_BYTE, lookup_table); 
		fLookupTextureReprocessed = false;
	}

	lookup_texture->parameter(GL_TEXTURE_MIN_FILTER, GL_NEAREST);
	lookup_texture->parameter(GL_TEXTURE_MAG_FILTER, GL_LINEAR);
	lookup_texture->parameter(GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
	lookup_texture->parameter(GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
}

// Initialize the necessary OpenGL extensions
//
void hwToonShader_NV20::init_ext(const char * ext)
{
	if(!glh_init_extension(ext))
	{ cerr << "Failed to initialize " << ext << "!" << endl; exit(0); }
}

hwToonShader_NV20::hwToonShader_NV20()
{
	// Get an reference to the singleton texture cache.
	m_pTextureCache = MTextureCache::instance();

	init_ext("GL_ARB_multitexture");
	init_ext("GL_NV_register_combiners");
	init_ext("GL_NV_vertex_program");

	isDirectionalLight = true;	// light's rotation is connected to the lightRotation attr

	// Set the shininess and shininess scale to absurd values, so that the
	// look-up table automatically get recomputed during the first update.
	currentShininessValue = -1.0;
	currentShininessScale = -1.0;
	lookup_texture = NULL;
	lookup_table   = NULL;
	fLookupTextureReprocessed = false;

	// Initialize callbacks.
	fBeforeNewCB = 0;
	fBeforeOpenCB = 0;
	fBeforeRemoveReferenceCB = 0;
	fMayaExitingCB = 0;
	attachSceneCallbacks();

	// Initialize the vertex program ids...
	fVertexProgramsLoaded = false;
	fVertexProgramDirectional = 0;
	fVertexProgramPointDecay = 0;
	fVertexProgramPointNoDecay = 0;
	// All vertex programs will get allocated and loaded
	// during the first refresh.
}

hwToonShader_NV20::~hwToonShader_NV20()
{
	detachSceneCallbacks();
}

void releaseVertexProgram(GLuint* pVertexProgramId)
{
	// If the vertex program id is set...
	if (*pVertexProgramId > 0)
	{
		// Unbind any vertex program...
		glBindProgramNV(GL_VERTEX_PROGRAM_NV, 0);

		glDeleteProgramsNV(1, pVertexProgramId);

		// For sanity, set the id to 0.
		*pVertexProgramId = 0;
	}
}


void hwToonShader_NV20::releaseEverything()
{
	release_lookup_texture();

	// Release all loaded vertex programs.
	if (fVertexProgramsLoaded)
	{
		releaseVertexProgram(&fVertexProgramDirectional);
		releaseVertexProgram(&fVertexProgramPointDecay);
		releaseVertexProgram(&fVertexProgramPointNoDecay);
		fVertexProgramsLoaded = false;
	}

	// Release the texture cache through refcounting.
	m_pTextureCache->release();
}

void hwToonShader_NV20::attachSceneCallbacks()
{
	fBeforeNewCB  = MSceneMessage::addCallback(MSceneMessage::kBeforeNew,  releaseCallback, this);
	fBeforeOpenCB = MSceneMessage::addCallback(MSceneMessage::kBeforeOpen, releaseCallback, this);
	fBeforeRemoveReferenceCB = MSceneMessage::addCallback(MSceneMessage::kBeforeRemoveReference, 
														  releaseCallback, this);
	fMayaExitingCB = MSceneMessage::addCallback(MSceneMessage::kMayaExiting, releaseCallback, this);
}

/*static*/
void hwToonShader_NV20::releaseCallback(void* clientData)
{
	hwToonShader_NV20 *pThis = (hwToonShader_NV20*) clientData;
	pThis->releaseEverything();
}

void hwToonShader_NV20::detachSceneCallbacks()
{
	if (fBeforeNewCB)
		MMessage::removeCallback(fBeforeNewCB);
	if (fBeforeOpenCB)
		MMessage::removeCallback(fBeforeOpenCB);
	if (fBeforeRemoveReferenceCB)
		MMessage::removeCallback(fBeforeRemoveReferenceCB);
	if (fMayaExitingCB)
		MMessage::removeCallback(fMayaExitingCB);

	fBeforeNewCB = 0;
	fBeforeOpenCB = 0;
	fBeforeRemoveReferenceCB = 0;
	fMayaExitingCB = 0;
}

MStatus initializePlugin( MObject obj )
{ 
	MStatus   status;
	
	const MString UserClassify( "shader/surface/utility" );

	MFnPlugin plugin( obj, "Alias", "4.5", "Any");
	status = plugin.registerNode( "hwToonShader_NV20", hwToonShader_NV20::id, 
			                      hwToonShader_NV20::creator, hwToonShader_NV20::initialize,
								  MPxNode::kHwShaderNode, &UserClassify );
	if (!status) {
		status.perror("registerNode");
		return status;
	}

	return MS::kSuccess;
}

MStatus uninitializePlugin( MObject obj )
{
	MStatus   status;
	
	MFnPlugin plugin( obj );

	plugin.deregisterNode( hwToonShader_NV20::id );
	if (!status) {
		status.perror("deregisterNode");
		return status;
	}

	return MS::kSuccess;
}


void * hwToonShader_NV20::creator()
{
    return new hwToonShader_NV20();
}

// Initialize the plug-in. Called once when the plug-in is loaded.
// This mostly involve creating attributes.
MStatus hwToonShader_NV20::initialize()
{
    MFnNumericAttribute nAttr; 
	MStatus status;
	MFnTypedAttribute sAttr; // For string attributes

    // Create input attributes

    colorR = nAttr.create( "colorR", "cr",MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(1.0f);

    colorG = nAttr.create( "colorG", "cg",MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(0.5f);

    colorB = nAttr.create( "colorB", "cb",MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(0.5f);

    color = nAttr.create( "color", "c", colorR, colorG, colorB);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(1.0f, 0.5f, 0.5f);
    nAttr.setUsedAsColor(true);

    lightModelR = nAttr.create( "lightModelR", "c2r",MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(1.0f);

    lightModelG = nAttr.create( "lightModelG", "c2g",MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(1.0f);

    lightModelB = nAttr.create( "lightModelB", "c2b",MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(1.0f);

    lightModel = nAttr.create( "lightModel", "c2", lightModelR, lightModelG, lightModelB);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(1.0f, 1.0f, 1.0f);
    nAttr.setUsedAsColor(true);

    uCoord = nAttr.create( "uCoord", "u", MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(0.5f);

    vCoord = nAttr.create( "vCoord", "v", MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(0.5f);
 
    uvCoord = nAttr.create( "uvCoord","uv", uCoord, vCoord);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(0.5f, 0.5f );
    nAttr.setHidden(true);

    uBias = nAttr.create( "uBias", "bu", MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setMin(0.0f);
    nAttr.setMax(1.0f);
    nAttr.setKeyable(true);
    nAttr.setDefault(0.5f);

    vBias = nAttr.create( "vBias", "bv", MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setMin(0.0f);
    nAttr.setMax(1.0f);
    nAttr.setDefault(0.5f);

    uvFilterSizeX = nAttr.create( "uvFilterSizeX", "fsx", MFnNumericData::kFloat);
    nAttr.setStorable(false);
    nAttr.setReadable(true);
    nAttr.setWritable(true);
    nAttr.setHidden(true);

    uvFilterSizeY = nAttr.create( "uvFilterSizeY", "fsy", MFnNumericData::kFloat);
    nAttr.setStorable(false);
    nAttr.setReadable(true);
    nAttr.setWritable(true);
    nAttr.setHidden(true);

    uvFilterSize = nAttr.create("uvFilterSize","fs",uvFilterSizeX,uvFilterSizeY);
    nAttr.setStorable(false);
    nAttr.setReadable(true);
    nAttr.setWritable(true);
    nAttr.setHidden(true);

    cameraX = nAttr.create( "cameraX", "camx",MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(0.0f);

    cameraY = nAttr.create( "cameraY", "camy",MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(0.0f);

    cameraZ = nAttr.create( "cameraZ", "camz",MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(1.0f);

    camera = nAttr.create( "camera", "cam", cameraX, cameraY, cameraZ);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(0.0f, 0.0f, 1.0f);

    shininess = nAttr.create( "shininess", "sn", MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setMin(0.0f);
    nAttr.setMax(1.0f);
    nAttr.setDefault(0.5f);

    lightColorR = nAttr.create( "lightColorR", "lcr", MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(1.0f);

    lightColorG = nAttr.create( "lightColorG", "lcg", MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(1.0f);

    lightColorB = nAttr.create( "lightColorB", "lcb", MFnNumericData::kFloat);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(1.0f);

    lightColor = nAttr.create( "lightColor", "lc", lightColorR, lightColorG, lightColorB);
    nAttr.setStorable(true);
    nAttr.setKeyable(true);
    nAttr.setDefault(1.0f, 1.0f, 1.0f);
    nAttr.setUsedAsColor(true);


 // Add the attributes here

    addAttribute(color);
    addAttribute(lightModel);

    addAttribute(uvCoord);

    addAttribute(uBias);
    addAttribute(vBias);

    addAttribute(uvFilterSize);

	addAttribute(camera);
    addAttribute(shininess);
    addAttribute(lightColor);

    attributeAffects (colorR, outColor);
    attributeAffects (colorG, outColor);
    attributeAffects (colorB, outColor);
    attributeAffects (color,  outColor);
    attributeAffects (lightModelR, outColor);
    attributeAffects (lightModelG, outColor);
    attributeAffects (lightModelB, outColor);
    attributeAffects (lightModel,  outColor);
    attributeAffects (uCoord,  outColor);
    attributeAffects (vCoord,  outColor);
    attributeAffects (uvCoord, outColor);
    attributeAffects (uBias,   outColor);
    attributeAffects (vBias,   outColor);

	attributeAffects (cameraX,	outColor);
	attributeAffects (cameraY,	outColor);
	attributeAffects (cameraZ,	outColor);
	attributeAffects (camera,	outColor);

    attributeAffects (shininess,   outColor);
    attributeAffects (lightColorR, outColor);
    attributeAffects (lightColorG, outColor);
    attributeAffects (lightColorB, outColor);
    attributeAffects (lightColor,  outColor);

    return MS::kSuccess;
}


// This function gets called by Maya to evaluate the texture.
// See "Writing a shading node plug-in" in the documentation
// for more information.
//
MStatus hwToonShader_NV20::compute(
const MPlug&      plug,
      MDataBlock& block ) 
{ 
	// Get color and lightModel from the input block.
	// Get UV coordinates from the input block.
	
	bool k = false;
    k |= (plug==outColor);
    k |= (plug==outColorR);
    k |= (plug==outColorG);
    k |= (plug==outColorB);
    if( !k ) return MS::kUnknownParameter;

    MFloatVector resultColor(0.0,0.0,0.0);

    float&  u = block.inputValue( uCoord ).asFloat();
    float&  v = block.inputValue( vCoord ).asFloat();
    float& bu = block.inputValue( uBias ).asFloat();
    float& bv = block.inputValue( vBias ).asFloat();

    if ( bu <= 0.0 ) bu = 0.001f;
    if ( bv <= 0.0 ) bv = 0.001f;

    MFloatVector& surfaceColor  = block.inputValue( color ).asFloatVector();
    MFloatVector& surfaceColor2 = block.inputValue( lightModel ).asFloatVector();

    // normalize the UV coords
    u = u - int(u);
    v = v - int(v);

    resultColor = surfaceColor;

    // set ouput color attribute
    MDataHandle outColorHandle = block.outputValue( outColor );
    MFloatVector& outColor = outColorHandle.asFloatVector();
    outColor = resultColor;
    outColorHandle.setClean();

    return MS::kSuccess;
}


// To get 3 float values from the node attribute
//
MStatus hwToonShader_NV20::getFloat3(MObject attr, float value[3])
{
	MStatus status = MS::kSuccess;

	// Get the attr to use
	//
	MPlug	plug(thisMObject(), attr);

	MObject object;
	status = plug.getValue(object);
	if (!status)
	{
		status.perror("hwToonShader_NV20::getFloat3 plug.getValue.");
		return status;
	}

	MFnNumericData data(object, &status);
	if (!status)
	{
		status.perror("hwToonShader_NV20::getFloat3 construct data.");
		return status;
	}

	status = data.getData(value[0], value[1], value[2]);
	if (!status)
	{
		status.perror("hwToonShader_NV20::getFloat3 get values.");
		return status;
	}

	return status;
}

// To get a string value from the node attribute
//
MStatus hwToonShader_NV20::getString(MObject attr, MString &str)
{
	MPlug	plug(thisMObject(), attr);
	MStatus status = plug.getValue( str );

	return status;
}

/* virtual */
MStatus	hwToonShader_NV20::bind(const MDrawRequest& request, M3dView& view)
{
	MStatus status;

	// Get the decal and lightModel map file names
	//
	MString decalName = "";
	MString lightModelName  = "";

	ShadingConnection colorConnection(thisMObject(), request.multiPath().partialPathName(), "color");
	ShadingConnection lightModelConnection (thisMObject(), request.multiPath().partialPathName(), "lightModel");

	// If the lightModel attribute is ultimately connected to a file texture, find its filename.
	// otherwise use the default lightModel texture.
	if (lightModelConnection.type() == ShadingConnection::TEXTURE &&
		lightModelConnection.texture().hasFn(MFn::kFileTexture))
	{
		// Get the filename of the texture.
		MFnDependencyNode textureNode(lightModelConnection.texture());
		MPlug filenamePlug( lightModelConnection.texture(), textureNode.attribute(MString("fileTextureName")) );
		filenamePlug.getValue(lightModelName);
	}


	// Fail safe quit
	//
	if (lightModelName.length() == 0 )
	{
		view.beginGL();
		glPushAttrib( GL_ALL_ATTRIB_BITS );		// This might be too conservative
		glPushClientAttrib(GL_CLIENT_VERTEX_ARRAY_BIT);
		glColorMaterial(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE);
		glEnable(GL_COLOR_MATERIAL);
		glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
		view.endGL();
		return MS::kSuccess;
	}

	view.beginGL();

	glPushAttrib( GL_ALL_ATTRIB_BITS );
	glPushClientAttrib(GL_CLIENT_VERTEX_ARRAY_BIT);

    /* Starts Here... */
	
	// stage 0 -- lighting model texture
	glActiveTextureARB( GL_TEXTURE0_ARB );
	glEnable(GL_TEXTURE_2D);
	m_pTextureCache->bind(lightModelConnection.texture(), MTexture::RGBA, false);
	
	// With light color and intensity
	//
	if (colorConnection.type() != ShadingConnection::TEXTURE)
	{
		MColor color = colorConnection.constantColor();
		glColor4f(color.r, color.g, color.b, color.a);
	}
	
	// The register combiner will do the multiplication between
	// the fetched light model result and the base (vertex or decal-textured) color
	//
	glEnable(GL_REGISTER_COMBINERS_NV);

	glCombinerParameteriNV(GL_NUM_GENERAL_COMBINERS_NV, 1);

	
	float constColor0[4];
	constColor0[0] = constColor0[1] = constColor0[2] = constColor0[3] = 1.0;
	glCombinerParameterfvNV(GL_CONSTANT_COLOR0_NV, constColor0);
	

#ifndef DEBUGGING_VERTEX_PROGRAM
	// Combiner stage 0 does the illumination modulation on the vertex color
	//
	glCombinerInputNV(GL_COMBINER0_NV, GL_RGB, GL_VARIABLE_A_NV, GL_PRIMARY_COLOR_NV, GL_UNSIGNED_IDENTITY_NV, GL_RGB);
	glCombinerInputNV(GL_COMBINER0_NV, GL_RGB, GL_VARIABLE_B_NV, GL_TEXTURE0_ARB, GL_UNSIGNED_IDENTITY_NV, GL_RGB);
	glCombinerInputNV(GL_COMBINER0_NV, GL_RGB, GL_VARIABLE_C_NV, GL_TEXTURE0_ARB, GL_UNSIGNED_IDENTITY_NV, GL_ALPHA);
	glCombinerInputNV(GL_COMBINER0_NV, GL_RGB, GL_VARIABLE_D_NV, GL_TEXTURE0_ARB, GL_UNSIGNED_IDENTITY_NV, GL_ALPHA);

	glCombinerOutputNV(GL_COMBINER0_NV, GL_RGB, GL_SPARE1_NV, GL_DISCARD_NV, GL_DISCARD_NV, 
					   GL_NONE, GL_NONE, GL_FALSE, GL_FALSE, GL_FALSE);

#else
	// Simplified register combiners to help debugging vertex program.
	glCombinerInputNV(GL_COMBINER0_NV, GL_RGB, GL_VARIABLE_A_NV, GL_PRIMARY_COLOR_NV, GL_UNSIGNED_IDENTITY_NV, GL_RGB);
	glCombinerInputNV(GL_COMBINER0_NV, GL_RGB, GL_VARIABLE_B_NV, GL_CONSTANT_COLOR0_NV, GL_UNSIGNED_IDENTITY_NV, GL_RGB);
	glCombinerInputNV(GL_COMBINER0_NV, GL_RGB, GL_VARIABLE_C_NV, GL_TEXTURE0_ARB, GL_UNSIGNED_IDENTITY_NV, GL_ALPHA);
	glCombinerInputNV(GL_COMBINER0_NV, GL_RGB, GL_VARIABLE_D_NV, GL_TEXTURE3_ARB, GL_UNSIGNED_IDENTITY_NV, GL_ALPHA);

	glCombinerOutputNV(GL_COMBINER0_NV, GL_RGB, GL_SPARE1_NV, GL_DISCARD_NV, GL_DISCARD_NV, 
					   GL_NONE, GL_NONE, GL_FALSE, GL_FALSE, GL_FALSE);
#endif // DEBUGGING_VERTEX_PROGRAM

	// The final Combiner just pass through. May want to add fog later.
	//
	glFinalCombinerInputNV(GL_VARIABLE_A_NV, GL_ZERO, GL_UNSIGNED_IDENTITY_NV, GL_RGB);
	glFinalCombinerInputNV(GL_VARIABLE_B_NV, GL_ZERO, GL_UNSIGNED_IDENTITY_NV, GL_RGB);
	glFinalCombinerInputNV(GL_VARIABLE_C_NV, GL_ZERO, GL_UNSIGNED_IDENTITY_NV, GL_RGB);
	glFinalCombinerInputNV(GL_VARIABLE_D_NV, GL_SPARE1_NV, GL_UNSIGNED_IDENTITY_NV, GL_RGB);

	view.endGL();

	return MS::kSuccess;
}


/* virtual */
MStatus	hwToonShader_NV20::unbind(const MDrawRequest& request,
			   M3dView& view)
{
	view.beginGL();
	
	glDisable(GL_REGISTER_COMBINERS_NV);

	glActiveTextureARB( GL_TEXTURE0_ARB );
	glDisable(GL_TEXTURE_2D);

	glPopClientAttrib();
	glPopAttrib();

	view.endGL();

	return MS::kSuccess;
}

/* virtual */
MStatus	hwToonShader_NV20::geometry( const MDrawRequest& request,
								M3dView& view,
							    int prim,
								unsigned int writable,
								int indexCount,
								const unsigned int * indexArray,
								int vertexCount,
								const int * vertexIDs,
								const float * vertexArray,
								int normalCount,
								const float ** normalArrays,
								int colorCount,
								const float ** colorArrays,
								int texCoordCount,
								const float ** texCoordArrays)
{
	// We assume triangles here.
	//
	if (prim != GL_TRIANGLES)
		return MS::kSuccess;		

	view.beginGL();

	// Find out if we have a directional light before
	// loading the vertex program since we use a different
	// vertex program depending on whether the light is a directional
	// one or not
	//
	isDirectionalLight = true; // Assume is directional
	isNonAmbientLight = false;

	boolean useDefaultLight = false;

	unsigned int numLights;
	MDagPath lightPath;
	view.getLightCount( numLights );
	if (numLights)
	{
		M3dView::LightingMode mode;
		view.getLightingMode(mode);
		if (mode == M3dView::kLightDefault)
		{
			useDefaultLight = true;
			isDirectionalLight = true;
		}
		else
		{
			view.getLightPath( 0, lightPath );
			MObject lightObj = lightPath.node();

			isDirectionalLight = lightObj.hasFn( MFn::kDirectionalLight );
			isNonAmbientLight = lightObj.hasFn( MFn::kNonAmbientLight );
			if (isNonAmbientLight)
			{
				MFnNonAmbientLight mNonAmbientLight(lightObj);
				if (mNonAmbientLight.decayRate() == 0)
					isNonAmbientLight = false;
			}
		}
	}

	loadVertexProgramGL();

	// Bind and enable the appropriate vertex program,
	// depending on light type.
	//
	if (isDirectionalLight)
		glBindProgramNV(GL_VERTEX_PROGRAM_NV, fVertexProgramDirectional);
	else if (isNonAmbientLight)
		glBindProgramNV(GL_VERTEX_PROGRAM_NV, fVertexProgramPointDecay);
	else
		glBindProgramNV(GL_VERTEX_PROGRAM_NV, fVertexProgramPointNoDecay);

	// Assert if an error occurs after binding the vertex programs.
	GLenum error = glGetError();
	assert(error == GL_NO_ERROR);

	// Enable the vertex program.
	glEnable(GL_VERTEX_PROGRAM_NV);

	// Get object's inverse matrix (ie: from world to object space.)
	MDagPath objPath = request.multiPath();
	MMatrix objMatrix = objPath.inclusiveMatrixInverse();

	// Get the light direction in object space.
	// This code assumes that there is a directional light in the scene,
	// and that it is the first light in DAG order.
	//
	if (numLights)
	{
		// Handle default lighting mode
		if (useDefaultLight )
		{
			// Provide the direction to the vertex program (constant 11)
			glProgramParameter4fNV(GL_VERTEX_PROGRAM_NV, 11, 0, 0, 1, 1);
			glProgramParameter4fNV(GL_VERTEX_PROGRAM_NV, 9, 1,1,1,1);
		}
		else
		{
			view.getLightPath( 0, lightPath );
			MMatrix matrix = lightPath.inclusiveMatrix();

			isDirectionalLight = lightPath.node().hasFn( MFn::kDirectionalLight );

			// Get rotation of a directional light in object space
			if (isDirectionalLight)
			{
				// Get rotation in world space
				MVector lightDir(0,0,1); // origin
				lightDir *= matrix;

				// Transform into object space
				lightDir *= objMatrix;

				// Provide the direction to the vertex program (constant 11)
				glProgramParameter4fNV(GL_VERTEX_PROGRAM_NV, 11, lightDir.x, lightDir.y, lightDir.z, 1);
			}
			// Get the position of a non-directional light in object space
			else
			{
				MPoint lightPos(0,0,0); // origin
				lightPos *= matrix;

				// Transform into object space
				lightPos *= objMatrix;

				// Provide the position to the vertex program (constant 11)
				glProgramParameter4fNV(GL_VERTEX_PROGRAM_NV, 11, lightPos.x, lightPos.y, lightPos.z, 1);
			}

			MFnLight mLight(lightPath.node());

			// Set the light's color.
			MColor lightColor = mLight.color();
			float intensity = mLight.intensity();
			lightColor.r *= intensity;
			lightColor.g *= intensity;
			lightColor.b *= intensity;

			glProgramParameter4fNV(GL_VERTEX_PROGRAM_NV, 9, lightColor.r, 
								   lightColor.g, lightColor.b, 1);
		}
	}
	else
	{
		// Set some default values
		glProgramParameter4fNV(GL_VERTEX_PROGRAM_NV, 11, 0, 0, 1, 1);
		glProgramParameter4fNV(GL_VERTEX_PROGRAM_NV, 9, 1.0, 1.0, 1.0, 1);
	}

	// Find the camera position in geometry's object space
	float cameraPos[4] = {0.0f, 0.0f, 0.0f, 0.0f};
	{
		MDagPath camDag;
		view.getCamera(camDag);

		MPoint cameraInObject(0,0,0); 
		
		MMatrix cameraToWorldMatrix = camDag.inclusiveMatrix();

		cameraInObject *= cameraToWorldMatrix; // to world
		cameraInObject *= objMatrix;

		glProgramParameter4fNV(GL_VERTEX_PROGRAM_NV, 12, cameraInObject.x, cameraInObject.y, cameraInObject.z, 1);
	}

	// VERTEX REGISTERS (Attributes):
	// 0 - coord
	// 2 - normal
	glVertexAttribPointerNV( 0, 3, GL_FLOAT, 0, vertexArray );
	glVertexAttribPointerNV( 2, 3, GL_FLOAT, 0, normalArrays[0] );

	glEnableClientState( GL_VERTEX_ATTRIB_ARRAY0_NV );
	glEnableClientState( GL_VERTEX_ATTRIB_ARRAY2_NV );

	glDrawElements(GL_TRIANGLES, indexCount, GL_UNSIGNED_INT, indexArray);

	glDisableClientState( GL_VERTEX_ATTRIB_ARRAY0_NV );
	glDisableClientState( GL_VERTEX_ATTRIB_ARRAY2_NV );
	
	glDisable(GL_VERTEX_PROGRAM_NV);

	glClientActiveTextureARB(GL_TEXTURE0_ARB);

	view.endGL();

	return MS::kSuccess;
}

/* virtual */
int		hwToonShader_NV20::normalsPerVertex()
{
	return 1;
}

/* virtual */
int		hwToonShader_NV20::texCoordsPerVertex()
{
	return 1;
}

// Release the lookup texture/image.
void hwToonShader_NV20::release_lookup_texture()
{
	if (lookup_table)
	{
		delete lookup_table;
		lookup_table = NULL;
	}
	
	if (lookup_texture)
	{
		delete lookup_texture;
		lookup_table = NULL;
	}
}