Sprite Errors

[DarkShadow44]

Hello,
I've some Problems displaying sprites.
The sprites are displayed with the libnds API, but there are always inaccuracies (1 or 2 pixel) (the sprites are not symmetric).
Because of I'm using 16x16 sprites, it doesn't look fine. Sometimes there are black pixels in a sprite where it should be blue...
Can I do something against it, or is that a error of the DS hardware ?

[Sylus101]

It's highly unlikely that it's an issue with the DS Hardware. I would say most likely it's a palette problem.

How are you loading the sprites? Are you converting with grit?

[DarkShadow44]

Yes, but the problem is, if I take a screenshot and zoom in it looks right ...

Code: Select all

LoadSpritePal(1,1,eTeleporterPal,512);
CreateSpriteFromGrit(1,12,150,160,1,eTeleporterTiles,eTeleporterTilesLen,16,32);

Code: Select all

define VRAM_I_EXT_PALETTE ((_palette *)VRAM_I)

void UpdateSprite(int Screen, int Number)
{
	
	OamState* oam;
	if(Screen==MainScreen)
	{
		oam=&oamMain;
	}
	else
	{
		oam=&oamSub;
	}
	
	 oamSet(oam,
        Number,
          Sprites[Screen][Number].x, //X-Koordinate
        Sprites[Screen][Number].y,  //Y-Koordinate
         0,
         Sprites[Screen][Number].palette,  //use different palettes
          Sprites[Screen][Number].Size,
         SpriteColorFormat_256Color,
         Sprites[Screen][Number].gfx,
          Sprites[Screen][Number].rotset,
         false,
         false,         
         false, false,
         false   
         ); 
}


void LoadSpritePal(int Screen, int Number,  const unsigned short* PAL, int PalSize)
{
	if(Screen==MainScreen)
	{
		 // unlock vram (cannot write to vram while it is mapped as a palette)
		vramSetBankG(VRAM_G_LCD);

		dmaCopy(PAL,&VRAM_G_EXT_PALETTE[Number][0],PalSize);

		// set vram to ex palette
		vramSetBankG(VRAM_G_SPRITE_EXT_PALETTE);
	}
	else
	{	
		vramSetBankI(VRAM_I_LCD);
		
		dmaCopy(PAL,&VRAM_I_EXT_PALETTE[Number][0],PalSize);
		
		vramSetBankI(VRAM_I_SUB_SPRITE_EXT_PALETTE);
	}
}


void CreateSprite(int Screen, int Number,int x, int y, int palette, void* GFX,int GfxSize, int Width,int Height)
{
	OamState* oam;
	if(Screen==MainScreen)
	{
		oam=&oamMain;
	}
	else
	{
		oam=&oamSub;
	}
	
	Sprites[Screen][Number].x=x;
	Sprites[Screen][Number].y=y;
	
	Sprites[Screen][Number].Width=Width;
	Sprites[Screen][Number].Height=Height;
	Sprites[Screen][Number].Size=getSize(Width,Height);
	
	Sprites[Screen][Number].palette=palette;
	Sprites[Screen][Number].gfx=oamAllocateGfx(oam, getSize( Width,Height), SpriteColorFormat_256Color);
	
	Sprites[Screen][Number].rotset=-1;

	dmaCopy(GFX, Sprites[Screen][Number].gfx, GfxSize);
	
	 UpdateSprite(Screen,Number);
	 
}


void CreateSpriteFromGrit(int Screen, int Number,int x, int y, int palette, const unsigned int* GFX, int GfxSize , int Width,int Height)
{
	CreateSprite(Screen,Number,x,y,palette,(void*)GFX,GfxSize, Width, Height);
}

Grit code:

Code: Select all

#-------------------------------------------------------
# graphics in tile format
#-------------------------------------------------------
-gt
#-------------------------------------------------------
# graphics bit depth is 8 (256 color)
#-------------------------------------------------------
-gB8

-gTFF00FF