Update to v093r07 release.

byuu says:

Changelog:
- importing a game won't show message box on success
- importing a game will select the game that was imported in the list
  - caveat: GTK+ port doesn't seem to be removing focus from item 0 even
    though the selection is on item 2
- Game Boy audio reduced in volume by 50%
- Game Boy Advance audio reduced in volume by 50%
- Game Boy internally mixes audio at 2MHz now
- Game Boy Advance's Game Boy audio hardware internally mixes audio at
  2MHz now
- Game Boy Color doesn't sort sprites by X-coordinate
- Game Boy Color allows transparency on BGpriority pixels
  - caveat: this seems to allow sprites to appear on top of windows
- Game Boy Color VRAM DMA transfers 16 bytes in 8 clocks (or 16 clocks
  in double speed mode)
- Game Boy Color VRAM DMA masks low 4-bits of source and destination
  address
- Game Boy Color VRAM DMA only allows reads from ROM or RAM
- Game Boy Color VRAM DMA only allows writes to VRAM
- fixed a bug in dereferencing a nullptr from pObject::find(), should
  fix crash when pressing enter key on blank windows
- fixed Windows RadioItem selection
- Game Boy Advance color emulation code added

gba/apu/apu.cpp

@@ -25,7 +25,7 @@ void APU::Enter() {
 }
 
 void APU::main() {
-  for(unsigned n = 0; n < 128; n++) {
+  for(unsigned n = 0; n < 64; n++) {
     runsequencer();
   }
 
@@ -70,7 +70,7 @@ void APU::main() {
   if(regs.bias.amplitude == 3) lsample &= ~15, rsample &= ~15;
 
   if(cpu.regs.mode == CPU::Registers::Mode::Stop) lsample = 0, rsample = 0;
-  interface->audioSample(sclamp<16>(lsample << 7), sclamp<16>(rsample << 7));  //should be <<5, use <<7 for added volume
+  interface->audioSample(sclamp<16>(lsample << 6), sclamp<16>(rsample << 6));  //should be <<5, use <<6 for added volume
   step(512);
 }
 

gba/apu/noise.cpp

@@ -1,6 +1,6 @@
 unsigned APU::Noise::divider() const {
-  if(divisor == 0) return 8;
-  return divisor * 16;
+  if(divisor == 0) return 4;
+  return divisor * 8;
 }
 
 void APU::Noise::run() {

gba/apu/registers.hpp

@@ -128,7 +128,7 @@ struct Sequencer {
   uint1 enable[4];
   uint1 masterenable;
 
-  uint13 base;
+  uint12 base;
   uint3 step;
   int16 lsample;
   int16 rsample;

gba/apu/square.cpp

@@ -1,6 +1,6 @@
 void APU::Square::run() {
   if(period && --period == 0) {
-    period = 4 * (2048 - frequency);
+    period = 2 * (2048 - frequency);
     phase++;
     switch(duty) {
     case 0: signal = (phase == 6); break;  //_____-_

gba/apu/square1.cpp

@@ -10,7 +10,7 @@ void APU::Square1::runsweep(bool update) {
   } else if(sweep.shift && update) {
     shadowfrequency = updatefrequency;
     frequency = updatefrequency;
-    period = 4 * (2048 - frequency);
+    period = 2 * (2048 - frequency);
   }
 }
 
@@ -64,7 +64,7 @@ void APU::Square1::write(unsigned addr, uint8 byte) {
 
     if(initialize) {
       enable = envelope.dacenable();
-      period = 4 * (2048 - frequency);
+      period = 2 * (2048 - frequency);
       envelope.period = envelope.frequency;
       volume = envelope.volume;
       shadowfrequency = frequency;

gba/apu/square2.cpp

@@ -32,7 +32,7 @@ void APU::Square2::write(unsigned addr, uint8 byte) {
 
     if(initialize) {
       enable = envelope.dacenable();
-      period = 4 * (2048 - frequency);
+      period = 2 * (2048 - frequency);
       envelope.period = envelope.frequency;
       volume = envelope.volume;
     }

gba/apu/wave.cpp

@@ -1,6 +1,6 @@
 void APU::Wave::run() {
   if(period && --period == 0) {
-    period = 2 * (2048 - frequency);
+    period = 1 * (2048 - frequency);
     patternsample = pattern[patternbank * 16 + patternaddr++];
     if(patternaddr == 0) patternbank ^= mode;
   }
@@ -55,7 +55,7 @@ void APU::Wave::write(unsigned addr, uint8 byte) {
 
     if(initialize) {
       enable = dacenable;
-      period = 2 * (2048 - frequency);
+      period = 1 * (2048 - frequency);
       patternaddr = 0;
       patternbank = mode ? (uint1)0 : bank;
     }

gba/video/video.cpp

@@ -7,13 +7,51 @@ Video video;
 void Video::generate_palette(bool color_emulation) {
   //todo: implement LCD color emulation
   for(unsigned color = 0; color < (1 << 15); color++) {
-    uint5 b = color >> 10;
-    uint5 g = color >>  5;
-    uint5 r = color >>  0;
+    unsigned B = (color >> 10) & 31;
+    unsigned G = (color >>  5) & 31;
+    unsigned R = (color >>  0) & 31;
 
-    uint16 R = r << 11 | r << 6 | r << 1 | r >> 4;
-    uint16 G = g << 11 | g << 6 | g << 1 | g >> 4;
-    uint16 B = b << 11 | b << 6 | b << 1 | b >> 4;
+    if(color_emulation) {
+      R = curve[R];
+      G = curve[G];
+      B = curve[B];
+
+      unsigned Rr = R * 16;
+      unsigned Gr = R *  4;
+      unsigned Br = R *  4;
+
+      unsigned Rg = G *  8;
+      unsigned Gg = G * 16;
+      unsigned Bg = G *  8;
+
+      unsigned Rb = B *  0;  //intentionally always zero
+      unsigned Gb = B *  8;
+      unsigned Bb = B * 16;
+
+      if(Rr < Rg) std::swap(Rr, Rg);
+      if(Rr < Rb) std::swap(Rr, Rb);
+      if(Rg < Rb) std::swap(Rg, Rb);
+
+      if(Gr < Gg) std::swap(Gr, Gg);
+      if(Gr < Gb) std::swap(Gr, Gb);
+      if(Gg < Gb) std::swap(Gg, Gb);
+
+      if(Br < Bg) std::swap(Br, Bg);
+      if(Br < Bb) std::swap(Br, Bb);
+      if(Bg < Bb) std::swap(Bg, Bb);
+
+      R = (((4 * Rr + 2 * Rg + Rb) * 160) >> 14) + 32;
+      G = (((4 * Gr + 2 * Gg + Gb) * 160) >> 14) + 32;
+      B = (((4 * Br + 2 * Bg + Bb) * 160) >> 14) + 32;
+
+      R = R << 8 | R;
+      G = G << 8 | G;
+      B = B << 8 | B;
+    } else {
+      R = R << 11 | R << 6 | R << 1 | R >> 4;
+      G = G << 11 | G << 6 | G << 1 | G >> 4;
+      B = B << 11 | B << 6 | B << 1 | B >> 4;
+    }
 
     palette[color] = interface->videoColor(color, R, G, B);
   }
@@ -27,4 +65,11 @@ Video::~Video() {
   delete[] palette;
 }
 
+const uint8 Video::curve[32] = {
+  0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0e, 0x10, 0x12,
+  0x14, 0x16, 0x18, 0x1c, 0x20, 0x28, 0x38, 0x38,
+  0x40, 0x48, 0x50, 0x58, 0x60, 0x68, 0x70, 0x80,
+  0x88, 0x90, 0xa0, 0xb0, 0xc0, 0xd0, 0xe0, 0xf0,
+};
+
 }

gba/video/video.hpp

@@ -4,6 +4,9 @@ struct Video {
 
   Video();
   ~Video();
+
+private:
+  static const uint8 curve[32];
 };
 
 extern Video video;