empathicqubit/langtoncant
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

this is not correct but it is drawing on the screen

Browse source
This commit is contained in:
Bjorn Einar Bjarntes 2021-12-18 17:18:48 +01:00
parent 5f55357441
commit 8f40d18f9a
1 changed files with 3 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
src/main.c
View file

@ -44,12 +44,14 @@ int isPositionWhite(long x, int y)
return 0; // 0 er false... return 0; // 0 er false...
} }
// https://archive.org/details/The_Graphics_Book_for_the_Commodore_64/page/n129/
void setPositionBlack(unsigned short x, BYTE y) void setPositionBlack(unsigned short x, BYTE y)
{ {
int ra = 320 * (int)(y/8) + (y & 7); int ra = 320 * (int)(y/8) + (y & 7);
int ba = 8 * (int)(x/8); int ba = 8 * (int)(x/8);
int ma = 2^(7-(x & 7)); int ma = 2^(7-(x & 7));
int ad = ma+ra+ba; int sa = 0x2000;
int ad = sa+ra+ba;
*(BYTE*)(ad) = *(BYTE*)(ad) | ma; *(BYTE*)(ad) = *(BYTE*)(ad) | ma;
} }