Gameboy Development Forum

Ardis · 2019-08-10 12:08:16

I've run across a little hiccup in my game I'm working on. To conserve sprites (since there are a few metasprites and small bullet sprites flying around,) I'm trying to run my HUD on the window layer. I got a placeholder HUD made where the character's health is represented by three icons for each health beyond 1 (which is represented by 0 icons.)

I'm also planning to track the player's progress and score on a given level.

I'm trying to make the HUD function for health work off a switch with each case being the possible values for health (0-4 currently) which will change the window layer tiles with the tiles for an empty health unit and a filled health unit.

The only command I know for changing window layer tiles is set_win_tiles which, if it works how I think it does, would require me to update the entire HUD based on an existing map. I don't think it will let me update a single tile.

Or would I be better off using sprites over the window layer for those details?

Robbi_Blechdose · 2019-08-10 12:40:59

Here's a function from my game which I use to place single tile:

Code:

void setWindowTile(int x, int y, UINT8 tile)
{
    set_win_tiles(x, y, 1, 1, tiles + tile); //Display the tile
}

The "tiles" variable is just a list of numbers from 0 to 255:

Code:

const unsigned char tiles[] =
{
    0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
    36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70,
    71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105,
    106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130,
    131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155,
    156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180,
    181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205,
    206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 230,
    231, 232, 233, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 249, 250, 251, 252, 253, 254, 255
};

I hope this is helpful in your case.
The reason we do it with the array is this: The function expects a pointer to a tile index (or possibly an array of them). The addition "tiles + tile" creates an address pointing to the number in the array you want.

Last edited by Robbi_Blechdose (2019-08-10 12:42:15)

Ardis · 2019-08-10 13:39:50

It worked! Thank you!

Gameboy Development Forum

#1 2019-08-10 12:08:16

Changing individual window layer tiles

#2 2019-08-10 12:40:59

Re: Changing individual window layer tiles

Code:

Code:

#3 2019-08-10 13:39:50

Re: Changing individual window layer tiles

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