// Example 1

#include <libps.h>						// Contains all net yaroze functions
#include "pad.h"						// Contains pad definitions, for use with reading pads

#define Screen_Width    (320)				// Screen resolution definitions
#define Screen_Height   (240)

#define Sprite_Mem_Addr      (0x80090000)      // memory address of sprite

#define OT_LENGTH (2)						//Ordering Table length
#define NUM_OF_SPRITES (1)						// Used to calculate packet size
#define MAX_NUM_SPRITES (NUM_OF_SPRITES + 1)	// Used to calculate packet size

GsOT            WorldOT[2];					// OT headers
GsOT_TAG        OTTags[2][1<<OT_LENGTH];	// OT units

PACKET          GpuPacketArea[2][10*1024];	// Packet area

GsSPRITE sprite;		// Structure to handle sprite

int    activeBuff;		// Variable to keep track of what buffer is in use

u_long PadStatus ;		// Variable to record what is inputted by the joy pad

// PROTOTYPE FUNCTIONS 
void InitGraphics();	
void InitSprite(GsSPRITE*,int,int,u_long);	
void RenderPrepare();
void RenderFinish();
								
// MAIN FUNCTION

void main()
{

	InitGraphics();		// Initialises the graphics system
    PadInit();	// Initialises Pad buffers, defined in pad.h
    InitSprite(&sprite,(Screen_Width/2),(Screen_Height/2),Sprite_Mem_Addr); // Sets sprite info
    
	PadStatus = PadRead() ;	// Reads current state of pad into PadStatus

    while(!(PadStatus&PADselect))	// Repeat until select on pad 1 is pressed
    {
		RenderPrepare();
                
        GsSortSprite(&sprite,&WorldOT[activeBuff],0);	// Sort sprite into OT

		RenderFinish();
		
		PadStatus = PadRead();
	}

    ResetGraph(0);	// Resets the drawing and display enviroment
}

void InitGraphics()
{
	int i;		// Counter used to set OTs

    SetVideoMode(MODE_PAL);	// Sets playstation to PAL signalling system
    // Initialises the graphic system
    GsInitGraph(Screen_Width, Screen_Height, GsOFSGPU, 0, 0);
    // Sets the top-left position of each frame buffer
    GsDefDispBuff(0,0,0,Screen_Height);

	// Ordering Table Initialisation
    for(i=0;i<2;i++)
    {
    	// Sets the resolution (length) of the OT
    	WorldOT[i].length = OT_LENGTH;
    	// Sets the OT headers to point to the start of OT units
    	WorldOT[i].org = OTTags[i];
    }	// End of OT Initialisation

}

void InitSprite(GsSPRITE *sprite, int tx, int ty, u_long tmemaddr)
{
        RECT rect;			// Create a RECT structure
        GsIMAGE timdata ;	// Create a GsIMAGE structure
        int tmp1,tmp2;		// Used to store colour info about tim

        // Setup Sprite

		// Copy tim file info into a GsIMAGE structure, timdata
        GsGetTimInfo((u_long*)(tmemaddr+4),&timdata);

		// Calculate tim colour info
		// Case 0 : 16 colour, Case 1 : 256 colour, Case 2 : true colour
		switch(timdata.pmode&3)
		{
			case 0 : {tmp1 = 0; tmp2 = 4; break;}
			case 1 : {tmp1 = 1; tmp2 = 2; break;}
			case 2 : {tmp1 = 2; tmp2 = 1; break;}
		}

		// Load pixel info into frame buffer
        rect.x=timdata.px;
        rect.y=timdata.py;
        rect.w=timdata.pw;
        rect.h=timdata.ph;
        LoadImage(&rect, timdata.pixel);

		// if tim has a clut, then load it into the frame buffer and set clut position is sprite
		if (!(tmp1==2))
		{
        	rect.x=timdata.cx;
        	rect.y=timdata.cy;
        	rect.w=timdata.cw;
        	rect.h=timdata.ch;
        	
        	LoadImage(&rect, timdata.clut);
        	
        	sprite->cx = timdata.cx;
        	sprite->cy = timdata.cy;
        }
        
        // Set Sprite attribute to specify colour depth
        sprite->attribute = (1<<24);
		// Set Screen position of sprite
        sprite->x = tx;
        sprite->y = ty;
        // Set width and height of sprite
        sprite->w = (timdata.pw*tmp2);
        sprite->h = (timdata.ph);
        // Get texture page sprite is on
        sprite->tpage = GetTPage(tmp1,0,timdata.px,timdata.py);
        // Set texture page offset from top-left of page
        sprite->u = timdata.px%64;
        sprite->v = timdata.py%256;
		// Set sprite brightness to normal
        sprite->r = sprite->g = sprite->b = 128;
		// Set sprite rotation point to center
        sprite->mx = (sprite->w/2);
        sprite->my = (sprite->h/2);
        // Set sprite size and orientation to normal
        sprite->scalex = ONE;
        sprite->scaley = ONE;
        sprite->rotate = 0;

}

void RenderPrepare()
{
	// Stores what buffer is in use, in activeBuff
   	activeBuff = GsGetActiveBuff();
	// Initialises the OT
    GsClearOt(0,0,&WorldOT[activeBuff]);
	// Sets drawing command storage address
    GsSetWorkBase((PACKET *)GpuPacketArea[activeBuff]);

}

void RenderFinish()
{
    // Waits for drawing to be completed
    DrawSync(0);
	// Waits for vertical synchronisation before moving on
    VSync(0);
	// Swaps display buffers
    GsSwapDispBuff();
	// Registers a drawing clear command in the OT
    GsSortClear(0,0,0,&WorldOT[activeBuff]);
	// Executes the drawing commands in the OT
    GsDrawOt(&WorldOT[activeBuff]);
}