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Hi all, me again.
Working from gbajunkies Tile/map tutorial I'm trying to display a 8*8 sprite.
As seperate programs I can draw a sprite, and display a BG. But when I try and put them together it doesnt work.
If I set the OAMData to 0x6010000 and sprite attribute 2 to 0, I get artifacts in the top left corner.
If I set OAMData to 0x6014000 and attribute 2 to 512 i get nothing but the Bg.

here's the code that draws the bg

Code:

SetMode(MODE_1 | OBJ_ENABLE | OBJ_MAP_1D);

bg2.number = 2;          //background number 0-3
bg2.charBaseBlock = 0; //tile data position
bg2.screenBaseBlock = 28;    //map data position on 2Kb boundary
bg2.colorMode = BG_COLOR_256; //256-colour background
bg2.size = ROTBG_SIZE_256x256; //size of map
bg2.mosaic = 0; //not enabled
bg2.x_scroll = 120;       //scrolling variables
bg2.y_scroll = 80;

EnableBackground(&bg2);

for(loop = 0; loop < 256; loop++){
   BGPaletteMem[loop] = tilesPalette[loop];
}

for(loop = 0; loop < tiles_WIDTH * tiles_HEIGHT /2; loop++)
   bg2.tileData[loop] = tilesData[loop];

temp = (u16*)New;
for(loop = 0; loop < 32*32/2; loop++)
   bg2.mapData[loop] = temp[loop];

followed by the code that should draw the sprite

Code:

for (loop = 0; loop < 256; loop++)
   OBJPaletteMem[loop] = sPalette[loop];

InitializeSprites();

sprites[0].attribute0 = COLOR_256 | SQUARE | 80;
sprites[0].attribute1 = SIZE_8 | 40;
sprites[0].attribute2 = 0;

for(loop = 0; loop < 8*8/2; loop++)
   {
      OAMData[loop] = sData[loop];
}

sorry for being such a noob but any help would be greatly appreciated.
Although at this rate, the thing I come up with at the end will be a mix and match of board posts!
thanks again.

uh duh!
Wasnt copying OAM in the main loop!!

gbadev.org forum archive

Beginners > sprites not working with my mode 2 bg

#9010 - immortalninjak - Sat Jul 26, 2003 1:41 pm

#9052 - immortalninjak - Sun Jul 27, 2003 11:28 am