vbagx/source/vba/gba/Mode4.cpp
2009-03-04 06:53:25 +00:00

379 lines
9.0 KiB
C++

/*
Mode 4 is a 256 colour bitmap graphics mode with 2 swappable pages.
It has a single layer, background layer 2, the same size as the screen.
It doesn't support scrolling, flipping, rotation or tiles.
These routines only render a single line at a time, because of the way the GBA does events.
*/
#include "GBA.h"
#include "GBAGfx.h"
#include "Globals.h"
void mode4RenderLine()
{
u16 *palette = (u16 *)paletteRAM;
if(DISPCNT & 0x0080) {
for(int x = 0; x < 240; x++) {
lineMix[x] = 0x7fff;
}
gfxLastVCOUNT = VCOUNT;
return;
}
if(layerEnable & 0x400) {
int changed = gfxBG2Changed;
if(gfxLastVCOUNT > VCOUNT)
changed = 3;
gfxDrawRotScreen256(BG2CNT, BG2X_L, BG2X_H, BG2Y_L, BG2Y_H,
BG2PA, BG2PB, BG2PC, BG2PD,
gfxBG2X, gfxBG2Y, changed,
line2);
}
gfxDrawSprites(lineOBJ);
u32 backdrop;
if(customBackdropColor == -1) {
backdrop = (READ16LE(&palette[0]) | 0x30000000);
} else {
backdrop = ((customBackdropColor & 0x7FFF) | 0x30000000);
}
for(int x = 0; x < 240; x++) {
u32 color = backdrop;
u8 top = 0x20;
if(line2[x] < color) {
color = line2[x];
top = 0x04;
}
if((u8)(lineOBJ[x]>>24) < (u8)(color >> 24)) {
color = lineOBJ[x];
top = 0x10;
}
if((top & 0x10) && (color & 0x00010000)) {
// semi-transparent OBJ
u32 back = backdrop;
u8 top2 = 0x20;
if(line2[x] < back) {
back = line2[x];
top2 = 0x04;
}
if(top2 & (BLDMOD>>8))
color = gfxAlphaBlend(color, back,
coeff[COLEV & 0x1F],
coeff[(COLEV >> 8) & 0x1F]);
else {
switch((BLDMOD >> 6) & 3) {
case 2:
if(BLDMOD & top)
color = gfxIncreaseBrightness(color, coeff[COLY & 0x1F]);
break;
case 3:
if(BLDMOD & top)
color = gfxDecreaseBrightness(color, coeff[COLY & 0x1F]);
break;
}
}
}
lineMix[x] = color;
}
gfxBG2Changed = 0;
gfxLastVCOUNT = VCOUNT;
}
void mode4RenderLineNoWindow()
{
u16 *palette = (u16 *)paletteRAM;
if(DISPCNT & 0x0080) {
for(int x = 0; x < 240; x++) {
lineMix[x] = 0x7fff;
}
gfxLastVCOUNT = VCOUNT;
return;
}
if(layerEnable & 0x400) {
int changed = gfxBG2Changed;
if(gfxLastVCOUNT > VCOUNT)
changed = 3;
gfxDrawRotScreen256(BG2CNT, BG2X_L, BG2X_H, BG2Y_L, BG2Y_H,
BG2PA, BG2PB, BG2PC, BG2PD,
gfxBG2X, gfxBG2Y, changed,
line2);
}
gfxDrawSprites(lineOBJ);
u32 backdrop;
if(customBackdropColor == -1) {
backdrop = (READ16LE(&palette[0]) | 0x30000000);
} else {
backdrop = ((customBackdropColor & 0x7FFF) | 0x30000000);
}
for(int x = 0; x < 240; x++) {
u32 color = backdrop;
u8 top = 0x20;
if(line2[x] < color) {
color = line2[x];
top = 0x04;
}
if((u8)(lineOBJ[x]>>24) < (u8)(color >> 24)) {
color = lineOBJ[x];
top = 0x10;
}
if(!(color & 0x00010000)) {
switch((BLDMOD >> 6) & 3) {
case 0:
break;
case 1:
{
if(top & BLDMOD) {
u32 back = backdrop;
u8 top2 = 0x20;
if(line2[x] < back) {
if(top != 0x04) {
back = line2[x];
top2 = 0x04;
}
}
if((u8)(lineOBJ[x]>>24) < (u8)(back >> 24)) {
if(top != 0x10) {
back = lineOBJ[x];
top2 = 0x10;
}
}
if(top2 & (BLDMOD>>8))
color = gfxAlphaBlend(color, back,
coeff[COLEV & 0x1F],
coeff[(COLEV >> 8) & 0x1F]);
}
}
break;
case 2:
if(BLDMOD & top)
color = gfxIncreaseBrightness(color, coeff[COLY & 0x1F]);
break;
case 3:
if(BLDMOD & top)
color = gfxDecreaseBrightness(color, coeff[COLY & 0x1F]);
break;
}
} else {
// semi-transparent OBJ
u32 back = backdrop;
u8 top2 = 0x20;
if(line2[x] < back) {
back = line2[x];
top2 = 0x04;
}
if(top2 & (BLDMOD>>8))
color = gfxAlphaBlend(color, back,
coeff[COLEV & 0x1F],
coeff[(COLEV >> 8) & 0x1F]);
else {
switch((BLDMOD >> 6) & 3) {
case 2:
if(BLDMOD & top)
color = gfxIncreaseBrightness(color, coeff[COLY & 0x1F]);
break;
case 3:
if(BLDMOD & top)
color = gfxDecreaseBrightness(color, coeff[COLY & 0x1F]);
break;
}
}
}
lineMix[x] = color;
}
gfxBG2Changed = 0;
gfxLastVCOUNT = VCOUNT;
}
void mode4RenderLineAll()
{
u16 *palette = (u16 *)paletteRAM;
if(DISPCNT & 0x0080) {
for(int x = 0; x < 240; x++) {
lineMix[x] = 0x7fff;
}
gfxLastVCOUNT = VCOUNT;
return;
}
bool inWindow0 = false;
bool inWindow1 = false;
if(layerEnable & 0x2000) {
u8 v0 = WIN0V >> 8;
u8 v1 = WIN0V & 255;
inWindow0 = ((v0 == v1) && (v0 >= 0xe8));
if(v1 >= v0)
inWindow0 |= (VCOUNT >= v0 && VCOUNT < v1);
else
inWindow0 |= (VCOUNT >= v0 || VCOUNT < v1);
}
if(layerEnable & 0x4000) {
u8 v0 = WIN1V >> 8;
u8 v1 = WIN1V & 255;
inWindow1 = ((v0 == v1) && (v0 >= 0xe8));
if(v1 >= v0)
inWindow1 |= (VCOUNT >= v0 && VCOUNT < v1);
else
inWindow1 |= (VCOUNT >= v0 || VCOUNT < v1);
}
if(layerEnable & 0x400) {
int changed = gfxBG2Changed;
if(gfxLastVCOUNT > VCOUNT)
changed = 3;
gfxDrawRotScreen256(BG2CNT, BG2X_L, BG2X_H, BG2Y_L, BG2Y_H,
BG2PA, BG2PB, BG2PC, BG2PD,
gfxBG2X, gfxBG2Y, changed,
line2);
}
gfxDrawSprites(lineOBJ);
gfxDrawOBJWin(lineOBJWin);
u32 backdrop;
if(customBackdropColor == -1) {
backdrop = (READ16LE(&palette[0]) | 0x30000000);
} else {
backdrop = ((customBackdropColor & 0x7FFF) | 0x30000000);
}
u8 inWin0Mask = WININ & 0xFF;
u8 inWin1Mask = WININ >> 8;
u8 outMask = WINOUT & 0xFF;
for(int x = 0; x < 240; x++) {
u32 color = backdrop;
u8 top = 0x20;
u8 mask = outMask;
if(!(lineOBJWin[x] & 0x80000000)) {
mask = WINOUT >> 8;
}
if(inWindow1) {
if(gfxInWin1[x])
mask = inWin1Mask;
}
if(inWindow0) {
if(gfxInWin0[x]) {
mask = inWin0Mask;
}
}
if((mask & 4) && (line2[x] < color)) {
color = line2[x];
top = 0x04;
}
if((mask & 16) && ((u8)(lineOBJ[x]>>24) < (u8)(color >>24))) {
color = lineOBJ[x];
top = 0x10;
}
if(color & 0x00010000) {
// semi-transparent OBJ
u32 back = backdrop;
u8 top2 = 0x20;
if((mask & 4) && line2[x] < back) {
back = line2[x];
top2 = 0x04;
}
if(top2 & (BLDMOD>>8))
color = gfxAlphaBlend(color, back,
coeff[COLEV & 0x1F],
coeff[(COLEV >> 8) & 0x1F]);
else {
switch((BLDMOD >> 6) & 3) {
case 2:
if(BLDMOD & top)
color = gfxIncreaseBrightness(color, coeff[COLY & 0x1F]);
break;
case 3:
if(BLDMOD & top)
color = gfxDecreaseBrightness(color, coeff[COLY & 0x1F]);
break;
}
}
} else if(mask & 32) {
switch((BLDMOD >> 6) & 3) {
case 0:
break;
case 1:
{
if(top & BLDMOD) {
u32 back = backdrop;
u8 top2 = 0x20;
if((mask & 4) && line2[x] < back) {
if(top != 0x04) {
back = line2[x];
top2 = 0x04;
}
}
if((mask & 16) && (u8)(lineOBJ[x]>>24) < (u8)(back >> 24)) {
if(top != 0x10) {
back = lineOBJ[x];
top2 = 0x10;
}
}
if(top2 & (BLDMOD>>8))
color = gfxAlphaBlend(color, back,
coeff[COLEV & 0x1F],
coeff[(COLEV >> 8) & 0x1F]);
}
}
break;
case 2:
if(BLDMOD & top)
color = gfxIncreaseBrightness(color, coeff[COLY & 0x1F]);
break;
case 3:
if(BLDMOD & top)
color = gfxDecreaseBrightness(color, coeff[COLY & 0x1F]);
break;
}
}
lineMix[x] = color;
}
gfxBG2Changed = 0;
gfxLastVCOUNT = VCOUNT;
}