// first and simplest 2d module



#include "2d1.h"


	// NO overall initialiser




void InitialiseTexture (long address)
{
	RECT rect;
	GsIMAGE timInfo;

	GsGetTimInfo((u_long *)(address+4), &timInfo);

	rect.x = timInfo.px;	
	rect.y = timInfo.py;		
	rect.w = timInfo.pw;	
	rect.h = timInfo.ph;	


	LoadImage(&rect, timInfo.pixel);

	if ( (timInfo.pmode>>3) & 0x01 ) 
		{
		rect.x = timInfo.cx;	
		rect.y = timInfo.cy;	
		rect.w = timInfo.cw;	
		rect.h = timInfo.ch;	

		LoadImage(&rect, timInfo.clut);
   		}

	DrawSync(0);
}





	// the second argument is a global declared next to the #define for
	// the TIM file main memory address;
	// it allows endless sprites to be easily linked to it later on
void ProperInitialiseTexture (long address, GsIMAGE* imageInfo)
{
	RECT rect;

		// +4 because we need to skip head of TIM file
	GsGetTimInfo( (u_long *)(address+4), imageInfo);

	rect.x = imageInfo->px;	
	rect.y = imageInfo->py;		
	rect.w = imageInfo->pw;	
	rect.h = imageInfo->ph;	

	LoadImage(	&rect, imageInfo->pixel);

		// if image needs a CLUT, load it up 
		// (pmode: 8 or 9 ==> texture is 4-bit or 8-bit)
	if ( (imageInfo->pmode>>3)&0x01) 
		{
		rect.x = imageInfo->cx;	
		rect.y = imageInfo->cy;	
		rect.w = imageInfo->cw;	
		rect.h = imageInfo->ch;	

		LoadImage( &rect, imageInfo->clut);
		}

		// wait for loading to finish
	DrawSync(0);
}





void LinkSpriteToImageInfo (GsSPRITE* sprite, GsIMAGE* imageInfo)
{
	int widthCompression;	  // on frame buffer
	int tPageType;
	int texturePageX, texturePageY, xOffset, yOffset;

	InitGsSprite(sprite);
		
	FindTopLeftOfTexturePage(imageInfo, 
		&texturePageX, &texturePageY, &xOffset, &yOffset);

	switch(imageInfo->pmode)
		{
		case 0:		   // 16-bit
			sprite->attribute |= SIXTEEN_BIT_MASK;		
			widthCompression = 1;
			tPageType = 2;	
			break;
		case 8:		   	 // 4-bit
			widthCompression = 4;
			tPageType = 0;
			sprite->cx = imageInfo->cx;
			sprite->cy = imageInfo->cy;	
			break;
		case 9:		   // 8-bit
			sprite->attribute |= EIGHT_BIT_MASK;		
			widthCompression = 2;
			tPageType = 1;
			sprite->cx = imageInfo->cx;
			sprite->cy = imageInfo->cy;		
			break;
		default:
			printf("Only 4, 8 and 16 bit modes supported\n");
			assert(FALSE);		// other modes not supported
		}

	sprite->tpage 
			= GetTPage(tPageType, 0, texturePageX, texturePageY);

	sprite->w = imageInfo->pw * widthCompression;
	sprite->h = imageInfo->ph;

	sprite->u = xOffset;
	sprite->v = yOffset;
}




void InitGsSprite (GsSPRITE* sprite)
{
		// initialise sprite to dummy
	sprite->attribute = 0;
	sprite->x = 0;
	sprite->y = 0;
	sprite->w = 0;
	sprite->h = 0;
	sprite->tpage = 0;
	sprite->u = 0;
	sprite->v = 0;
	sprite->cx = 0;
	sprite->cy = 0;
	sprite->r = 128;
	sprite->g = 128;
	sprite->b = 128;
	sprite->mx = 0;
	sprite->my = 0;
	sprite->scalex = ONE;
	sprite->scaley = ONE;
	sprite->rotate = 0;
}






	// find coords wrt tpage top left points
void FindTopLeftOfTexturePage (GsIMAGE* imageInfo, 
									int* x, int* y, int* u, int* v)
{
	int testX, testY;

	testX = imageInfo->px;
	testY = imageInfo->py;

	*u = 0;
	*v = 0;
	
	for (;;)
		{
		if (testX % 320 != 0)
			{
			testX--;
			(*u)++;
			}
		else
			break;
		}

	for (;;)
		{
		if (testY % 256 != 0)
			{
			testY--;
			(*v)++;
			}
		else
			break;
		}

	*x = testX;
	*y = testY;
}