/*---------------------------------------------------------------------------*
  Project:  VI trap filter demo
  File:     cross-color.c

  Copyright 2006 Nintendo.  All rights reserved.

  These coded instructions, statements, and computer programs contain
  proprietary information of Nintendo of America Inc. and/or Nintendo
  Company Ltd., and are protected by Federal copyright law.  They may
  not be disclosed to third parties or copied or duplicated in any form,
  in whole or in part, without the prior written consent of Nintendo.

  $Log: cross-color.c,v $
  Revision 1.1  07/22/2006 04:56:27  urata
  Initial checkin.

  $NoKeywords: $
 *---------------------------------------------------------------------------*/

#include <revolution.h>

#define NTSC      // if you change here, you can see PAL or M/PAL


#if defined(NTSC)
GXRenderModeObj* rmode = &GXNtsc480Int;
#elif defined(PAL)
GXRenderModeObj* rmode = &GXPal528Int;
#elif defined(EURGB60)
GXRenderModeObj* rmode = &GXEurgb60Hz480Int;
#else
GXRenderModeObj* rmode = &GXMpal480Int;
#endif


// for X frame buffer
static u8*  xfbA;
static u8*  xfbB;

/*---------------------------------------------------------------------------*
    Name:               allocateFB
    
    Description:        Allocates memory for two frame buffers
                                
    Arguments:          fbSize      each frame buffer size
    
    Returns:            none
 *---------------------------------------------------------------------------*/
static void allocateFB(u32 fbSize)
{
    void*       arenaLo;

    arenaLo = OSGetArenaLo();

    // allocate memory for frame buffer here.
    xfbA = (u8*)OSRoundUp32B(arenaLo);
    xfbB = (u8*)OSRoundUp32B(xfbA + fbSize);

    arenaLo = (void*)(xfbA + 2 * fbSize);
    OSSetArenaLo(arenaLo);
}



/*---------------------------------------------------------------------------*
  Name:         YuvPset

  Description:  Draw point

  Arguments:    posX            X coordinate
                posY            Y coordinate
                width           Stride of xfb
                xfb             Frame buffer address
                luma            Luma of point color
                u,v             Chroma of point color
                
  Returns:      None.
 *---------------------------------------------------------------------------*/
static void YuvPset(s32 posX, s32 posY, s32 width, u32 *xfb, u8 luma, u8 u, u8 v)
{
    u32 *ptr;
    u32 y1, y2;

    ptr = xfb + (posX>>1) + (width/2) * posY;

    if (posX & 1) 
    {
        y1 = (((*ptr) >> 24) & 0xFF ) ;
        y2 = luma;
    } 
    else 
    {
        y1 = luma;
        y2 = (((*ptr) >>  8) & 0xFF ) ;
    }
    *ptr = ((y1<<24) | (u<<16) | (y2<<8) | v);
}

/*---------------------------------------------------------------------------*
  Name:         YuvCircle

  Description:  Draw circle

  Arguments:    posX            Center of X coordinate
                posY            Center of Y coordinate
                width           Stride of xfb
                r               Radius
                xfb             Frame buffer address
                luma            Luma of point color
                u,v             Chroma of point color
                
  Returns:      None.
 *---------------------------------------------------------------------------*/
static void YuvCircle(s32 posX, s32 posY, s32 width, s32 r, u32 *xfb, u8 luma, u8 u, u8 v)
{
    int x, y, f;

    x = r;
    y = 0;
    f = -2 * r + 3;

    while (x >= y) {
        YuvPset(posX + x, posY + y, width, xfb, luma, u, v);
        YuvPset(posX - x, posY + y, width, xfb, luma, u, v);
        YuvPset(posX + x, posY - y, width, xfb, luma, u, v);
        YuvPset(posX - x, posY - y, width, xfb, luma, u, v);
        YuvPset(posX + y, posY + x, width, xfb, luma, u, v);
        YuvPset(posX - y, posY + x, width, xfb, luma, u, v);
        YuvPset(posX + y, posY - x, width, xfb, luma, u, v);
        YuvPset(posX - y, posY - x, width, xfb, luma, u, v);
        if (f >= 0) {
            x --;
            f -= x*4;
        }
        y++;
        f += 4*y + 2;
    }
}


/*---------------------------------------------------------------------------*
    Name:               DrawCircles
    
    Description:        Draw circles
                                
    Arguments:          width       Screen width
                        height      Screen height
                        fbSize      Size of the frame buffer
                        xfb             Frame buffer address

    Returns:            none
 *---------------------------------------------------------------------------*/
static void DrawCircles(s32 width, s32 height, u32 fbSize, u8* xfb)
{
    s32 xoffset;
    s32 yoffset;
    s32 r;
    u8 luma,u,v;
    
    luma = 0xEB;
    u = 0x80;
    v = 0x80;
    xoffset = width / 2;
    yoffset = height / 2;
    
    
    for(r=2; r<yoffset-3; r+=3)
    {
        YuvCircle(xoffset, yoffset, width, r, (u32 *)xfb, luma, u, v);
    }
    DCStoreRange((void*)xfb, fbSize);
}

/*---------------------------------------------------------------------------*
    Name:               DrawBlackScreen
    
    Description:        Draw black screen
                                
    Arguments:          fbSize      size of the frame buffer
                        xfb         frame buffer address

    Returns:            none
 *---------------------------------------------------------------------------*/
static void DrawBlackScreen(u32 fbSize, u8 *xfb )
{
    u16 *p = (u16 *)xfb;
    
    while(fbSize--)
    {
        *p++ = 0x1080; // 2 byte
    }
}

/*---------------------------------------------------------------------------*
    Name:               main
    
    Description:        Main function
                                
    Arguments:          none

    Returns:            none
 *---------------------------------------------------------------------------*/
void main(void)
{
    u32             frame;
    u32             fbSize;
    u8*             xfb;
    u32             first;
    u32             mode;
    PADStatus       pstat[PAD_MAX_CONTROLLERS];
    u32             plast=0;
    VIBool          trap_filter;
    
    OSInit();
    VIInit();
    PADInit();
    
    // Calculate frame buffer size.
    // Note that each line width should be a multiple of 16.
    fbSize = (u32)(VIPadFrameBufferWidth(rmode->fbWidth)
        * rmode->xfbHeight * VI_DISPLAY_PIX_SZ);

    allocateFB(fbSize);
    
    VIConfigure(rmode);

    // Need to "flush" so that the VI changes so far takes effect
    // from the following field
    VIFlush();
    VIWaitForRetrace();


    first = 1;
    frame = 0;
    
    mode=0;  // flip mode; 0 = disable trap filter, 1 = enable trap filter
    trap_filter=VI_DISABLE;
    OSReport("Disable Trap filter.\n");
    
    DrawBlackScreen(fbSize, xfbA);
    DrawBlackScreen(fbSize, xfbB);
    
    while(1)
    {
        PADRead(pstat);
        if ((pstat[0].button & PAD_BUTTON_A) && !(plast & PAD_BUTTON_A)) 
        {
            mode = 1 - mode;
            if (mode)
            {
                trap_filter = VI_ENABLE;
                OSReport("Enable Trap filter.\n");
            }
            else
            {
                trap_filter = VI_DISABLE;
                OSReport("Disable Trap filter.\n");
            }
        }
        
        xfb = (frame & 0x1)? xfbB : xfbA;

        DrawCircles( rmode->fbWidth, rmode->xfbHeight, fbSize, xfb);
        VISetNextFrameBuffer((void*)xfb );

        if (first == 1)
        {
            VISetBlack(FALSE);
            first = 0;
        }
        
        VISetTrapFilter(trap_filter);
        
        // Need to "flush" so that the VI changes so far takes effect
        // from the following field
        VIFlush();
        VIWaitForRetrace();
        

        plast = pstat[0].button;
        frame++;
    }
}