#11054 - mandarin - Wed Sep 24, 2003 8:01 pm
Hi all,
I have this problem I'm creating a little demo game...but I have a problem
my intro consists of a background in mode4 but my level is in mode1 and i'm having conflict anyone know what i can do to make this conflict stop.
#11059 - NoMis - Wed Sep 24, 2003 10:18 pm
You can switch mode at runtime. So you must go to mode4 and draw your intro picture. If you then go to your level you just have to set mode to mode1
NoMis
#11061 - mandarin - Wed Sep 24, 2003 11:04 pm
I do do that but for some reason when my level map loads it shows then flashes away
any ideas?
#11066 - tepples - Thu Sep 25, 2003 1:46 am
When switching from one of the rot/scale modes (mode 1 or mode 2) to one of the bitmapped modes (modes 3, 4, and 5) or back, make sure that you've set BG2's affine matrix properly. Try setting it to identity (pa=1<<8, pb=0, pc=0, pd=1<<8, x_origin=0, y_origin=0) and see if your maps come back.
_________________
-- Where is he?
-- Who?
-- You know, the human.
-- I think he moved to Tilwick.
#11083 - mandarin - Thu Sep 25, 2003 7:56 pm
explain in plain english...i'm a newbie explain plz
#11084 - tepples - Thu Sep 25, 2003 8:13 pm
Mode 1 is scaled and rotated using a matrix stored in hardware registers. If you do not know what this means, please re-read the rot/scale section of your favorite GBA programming tutorial.
It turns out that Mode 4 can be scaled and rotated using the same registers.
If your maps disappear immediately after they appear, you may not be setting the matrix properly. Try setting the matrix to the default value, which is the identity matrix. If you do not know what an identity matrix is, please consult a linear algebra textbook.
_________________
-- Where is he?
-- Who?
-- You know, the human.
-- I think he moved to Tilwick.
#11087 - mandarin - Thu Sep 25, 2003 9:11 pm
I get it to display the map now but the map looks weird it has like stripes with a weird icon in the left top corner.
#11089 - tepples - Thu Sep 25, 2003 9:15 pm
...run-on...
Can you provide a screenshot?
_________________
-- Where is he?
-- Who?
-- You know, the human.
-- I think he moved to Tilwick.
#11091 - mandarin - Thu Sep 25, 2003 9:40 pm
#11094 - tepples - Thu Sep 25, 2003 11:33 pm
Looks like either the background's Chr Base Block pointer is pointing into nowhere, or you forgot to copy your tile data into VRAM.
_________________
-- Where is he?
-- Who?
-- You know, the human.
-- I think he moved to Tilwick.