Gameboy Development Forum
Discussion about software development for the old-school Gameboys, ranging from the "Gray brick" to Gameboy Color
(Launched in 2008)
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#1 2017-06-02 22:00:28
help with background
I've been doing a bit of digging and I just cant seem to find what I'm looking for.
Pretty much I've set up a map using a tile collection of 8x8 tiles but I just cant work out how to properly use the map as a background.
Also, I've gone and set light grey to transparent so I can use white in some sprites, however when I put this in game the white I used in the sprites shows up as light grey, how do you set it to white outside of the tile editor?
Any help would be appreciated thanks.
UPDATE:
I've managed to get the background displaying (sort of) however it only shows up one sprite type instead of what its supposed to show.
Also, I still haven't worked out how to set white to non-transparent yet,
Last edited by jobalisk (2017-06-03 03:42:44)
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#2 2017-06-03 06:21:33
Re: help with background
To select another color than white as the transparent color, you have to set the sprite palette (OBP0 or OBP1) to the correct value.
Setting OBP0 to %11100001 will probably be correct in your case.
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#3 2017-06-03 14:51:48
Re: help with background
Thanks, any chance you could show me how to do that that in C?
Also, here's the code I'm using to load the background:
set_bkg_data(0,255, groundTiles);
VBK_REG = 1;
VBK_REG = 0;
set_bkg_tiles(0, 0, 20, 10, map01);
SHOW_BKG;
DISPLAY_ON;
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#4 2017-06-03 15:33:18
Re: help with background
Well, the code in C would be:
Code:
OBP0_REG = 0xE1; // $E1 = %11100001
The problem with the background is probably that you only load the upper 10 rows. Try this:
Code:
set_bkg_tiles(0, 0, 20, 18, map01); // 18 instead of only 10 lines.
Setting VBK_REG to 1 and immediately afterwards to 0 doesn't make much sense either but shouldn't be the cause for the problem.
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But keep in mind that the Game Boy screen only displays 20 x 18 tiles. So the last two rows won't be visible unless you add vertical scrolling to your game.