Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Make the PPU background color available and mirroring the pallet. #15

Open
wants to merge 1 commit into
base: master
Choose a base branch
from
Open

Make the PPU background color available and mirroring the pallet. #15

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
22 changes: 16 additions & 6 deletions Part #4 - PPU Backgrounds/olc2C02.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -51,7 +51,7 @@

Author
~~~~~~
David Barr, aka javidx9, �OneLoneCoder 2019
David Barr, aka javidx9, ©OneLoneCoder 2019
*/

#include "olc2C02.h"
Expand Down Expand Up @@ -206,7 +206,8 @@ olc::Sprite& olc2C02::GetPatternTable(uint8_t i, uint8_t palette)
{
// We can get the index value by simply adding the bits together
// but we're only interested in the lsb of the row words because...
uint8_t pixel = (tile_lsb & 0x01) + (tile_msb & 0x01);
// uint8_t pixel = (tile_lsb & 0x01) + (tile_msb & 0x01);
uint8_t pixel = (tile_lsb & 0x01) + ((tile_msb & 0x01) << 1);

// ...we will shift the row words 1 bit right for each column of
// the character.
Expand Down Expand Up @@ -524,10 +525,19 @@ void olc2C02::ppuWrite(uint16_t addr, uint8_t data)
else if (addr >= 0x3F00 && addr <= 0x3FFF)
{
addr &= 0x001F;
if (addr == 0x0010) addr = 0x0000;
if (addr == 0x0014) addr = 0x0004;
if (addr == 0x0018) addr = 0x0008;
if (addr == 0x001C) addr = 0x000C;
// if (addr == 0x0010) addr = 0x0000;
// if (addr == 0x0014) addr = 0x0004;
// if (addr == 0x0018) addr = 0x0008;
// if (addr == 0x001C) addr = 0x000C;
if ((addr == 0x0004) ||
(addr == 0x0008) ||
(addr == 0x000C) ||
(addr == 0x0010) ||
(addr == 0x0014) ||
(addr == 0x0018) ||
(addr == 0x001C)
) addr = 0x0000;

tblPalette[addr] = data;
}
}
Expand Down