#include "hair.h"

#include <stdio.h>

Hair::Hair()
{
	pDecal = NULL;

	pixelx = 0;
	pixely = 0;

	xangle = 0.0;
	yangle = 0.0;

	xpos = 0.0;
	ypos = 0.0;

	fWhiteDif[0] = 1.0;
	fWhiteDif[1] = 1.0;
	fWhiteDif[2] = 1.0;
	fWhiteDif[3] = 1.0;

	fBlackDif[0] = 0.0;
	fBlackDif[1] = 0.0;
	fBlackDif[2] = 0.0;
	fBlackDif[3] = 1.0;
}

Hair::~Hair()
{
}

void Hair::CreateDisplayList(GLuint *id)
{
	if ( id && ( ! (*id) ) )
	{
		GLfloat fPyrVerts[5][4] =
		{
			{ 0.0, 0.0, 0.0 },
			{ -HAIR_PYRAMID_WIDTH, -HAIR_PYRAMID_WIDTH, HAIR_PYRAMID_HEIGHT },
			{ -HAIR_PYRAMID_WIDTH,  HAIR_PYRAMID_WIDTH, HAIR_PYRAMID_HEIGHT },
			{  HAIR_PYRAMID_WIDTH,  HAIR_PYRAMID_WIDTH, HAIR_PYRAMID_HEIGHT },
			{  HAIR_PYRAMID_WIDTH, -HAIR_PYRAMID_WIDTH, HAIR_PYRAMID_HEIGHT },
		};

		// Only create the display list once

		GLfloat fPyramidAmb[]  = {0.0, 0.0, 0.0, 1.0};
		GLfloat fPyramidSpec[] = {1.0, 1.0, 1.0, 1.0};

		*id = glGenLists(1);

		glNewList(*id, GL_COMPILE);

		glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE,  fWhiteDif);
		glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT,  fPyramidAmb);
//		glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, fPyramidSpec);

		// Create a simple inverted pyramid
		glBegin(GL_TRIANGLES);

			// Sides
			glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE,  fWhiteDif);
			glVertex3fv(fPyrVerts[0]);
			glVertex3fv(fPyrVerts[1]);
			glVertex3fv(fPyrVerts[2]);

			glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE,  fBlackDif);
			glVertex3fv(fPyrVerts[0]);
			glVertex3fv(fPyrVerts[2]);
			glVertex3fv(fPyrVerts[3]);

			glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE,  fWhiteDif);
			glVertex3fv(fPyrVerts[0]);
			glVertex3fv(fPyrVerts[3]);
			glVertex3fv(fPyrVerts[4]);

			glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE,  fBlackDif);
			glVertex3fv(fPyrVerts[0]);
			glVertex3fv(fPyrVerts[4]);
			glVertex3fv(fPyrVerts[1]);

			// Cap
			glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE,  fBlackDif);
			glVertex3fv(fPyrVerts[1]);
			glVertex3fv(fPyrVerts[2]);
			glVertex3fv(fPyrVerts[3]);

			glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE,  fWhiteDif);
			glVertex3fv(fPyrVerts[1]);
			glVertex3fv(fPyrVerts[3]);
			glVertex3fv(fPyrVerts[4]);

		glEnd();

		glEndList();
	}

	// Set the internal id for this hair instance
	DisplayID = *id;
}

void Hair::Draw()
{
	glPushMatrix();

		glTranslatef( xpos, ypos, 0.0 );

		glRotatef( xangle, 1.0, 0.0, 0.0 );
		glRotatef( yangle, 0.0, 1.0, 0.0 );
		glCallList(DisplayID);

	glPopMatrix();
}

float Hair::PixelToPhysicalPos(GLuint pixel, float fPhysicalSize, GLuint nPixelSize)
{
	return ( (float) pixel + 0.5f ) * fPhysicalSize / ( (float) nPixelSize );
}

void Hair::SetPixelPos(GLuint x, GLuint y)
{
	pixelx = x;
	pixely = y;

	if (pDecal)
	{
		xpos = PixelToPhysicalPos(x, pDecal->fPhysicalTextureWidth,  pDecal->nPixelTextureWidth);
		ypos = PixelToPhysicalPos(y, pDecal->fPhysicalTextureHeight, pDecal->nPixelTextureHeight);

		SetAnglesWithPixelLoc(x, y);
/*
		float angle = 0.0;
		angle = GetAngleFromBytes(0, 0);
		angle = GetAngleFromBytes(0, 255);
		angle = GetAngleFromBytes(64, 0);
		angle = GetAngleFromBytes(128, 0);
		angle = GetAngleFromBytes(128, 128);
		angle = GetAngleFromBytes(150, 0);
		angle = GetAngleFromBytes(255, 0);
		angle = GetAngleFromBytes(255, 255);
*/
	}
}

void Hair::SetTextureInfo(Decal *pInput)
{
	pDecal = pInput;
}

void Hair::SetAnglesWithPixelLoc(GLuint x, GLuint y)
{
	GLubyte r, g, b, a;

	if (pDecal)
		pDecal->GetPixel(x, y, r, g, b, a);

	SetAnglesWithPixelColor(r, g, b, a);
}

void Hair::SetAnglesWithPixelColor(GLubyte r, GLubyte g, GLubyte b, GLubyte a)
{
	xangle = GetAngleFromBytes(r, g);
	yangle = GetAngleFromBytes(b, a);
}

float Hair::GetAngleFromBytes(GLubyte high, GLubyte low)
{
	float angle = 0.0;

	if ( ( high != 128 ) || low )
	{
		angle = (float) high - 128.0f;

		// Only bother computing the extra precision if the low byte is more than 0
		if (low)
			angle += (float) low / 255.0f;

		angle *= 90.0;

		if ( (high >= 0) && ( high <= 127 ) )
		{
			// left/down
			angle /= 128.0f;
		}
		else if ( (high >= 129) && ( high <= 255 ) )
		{
			// right/up
			angle /= 127.0f;
		}
	}

//	printf("high = %3d, low = %3d, angle = %10.5f\n", high, low, angle);

	return angle;
}