fixed framerate

fixed transparent pixels in sprites tweaks in rom bank changing
gonccalo · Apr 14, 2017 · 1bc3740 · 1bc3740
1 parent 8f0d5be
commit 1bc3740
Show file tree

Hide file tree

Showing 4 changed files with 27 additions and 9 deletions.
diff --git a/gameboygo/cpu.go b/gameboygo/cpu.go
@@ -300,6 +300,7 @@ func Reset() {
 	regs.l = 0x4D
 	regs.sp = 0xFFFE
 	regs.pc = 0x100
+	writeByte(0xFF04, 0xAB)
 	writeByte(0xFF05, 0x00)
 	writeByte(0xFF06, 0x00)
 	writeByte(0xFF07, 0x00)

diff --git a/gameboygo/main.go b/gameboygo/main.go
@@ -52,25 +52,25 @@ func main() {
 	if *fdebug {
 		for {
 			t := time.Now()
-			for CicleCounter = 0; (CicleCounter < CPU_FREQ); {
+			for CicleCounter = 0; (CicleCounter < (CPU_FREQ/60)); {
 				handleInput()
 				ExecuteDebug()
 				UpdateGPU(renderer, texture, cicles_op)
 			} 
-			fmt.Println(time.Second - time.Since(t))
-			time.Sleep(time.Second - time.Since(t))
+			fmt.Println((time.Second/60) - time.Since(t))
+			time.Sleep((time.Second/60) - time.Since(t))
 		}
 	} else{
 		for {
 			CicleCounter = 0
 			t := time.Now()
-			for ;(CicleCounter <= CPU_FREQ); {
+			for ;(CicleCounter <= (CPU_FREQ/60)); {
 				handleInput()
 				Execute()
 				UpdateGPU(renderer, texture, cicles_op)
 			} 
-			fmt.Println(time.Second - time.Since(t))
-			time.Sleep(time.Second - time.Since(t))
+			//fmt.Println((time.Second/60) - time.Since(t))
+			time.Sleep((time.Second/60) - time.Since(t))
 		}
 	}
 }

diff --git a/gameboygo/rom.go b/gameboygo/rom.go
@@ -94,11 +94,15 @@ func Load_rom(filename string) {
 
 func changeLRomBank(num uint8) {
 	if Head.cart_type == ROM_MBC1 || Head.cart_type == ROM_MBC1_RAM_BATT || Head.cart_type == ROM_MBC1_RAM{
+		actualRom := romBank 
 		romBank = romBank & 0xE0
 		romBank = romBank | (num & 0x1F)
 		if romBank == 0 {
 			romBank = 1
 		}
+		if actualRom == romBank {
+			return
+		}
 		if num := copy(ram[0x4000:0x8000], RomData[0x4000 * uint32(romBank):0x4000 * (uint32(romBank) + 1)]); num != 0x4000{
 			fmt.Printf("ERRO no bank, copiados %d\n", num)
 			return
@@ -108,11 +112,15 @@ func changeLRomBank(num uint8) {
 func changeHRomOrRamBank(num uint8) {
 	if Head.cart_type == ROM_MBC1 || Head.cart_type == ROM_MBC1_RAM_BATT || Head.cart_type == ROM_MBC1_RAM{
 		if bankMode == 0{
+			actualRom := romBank
 			romBank = romBank & 0x1F
 			romBank = romBank | ((num&0x03)<<5)
 			if romBank == 0 {
 				romBank = 1
 			}
+			if actualRom == romBank {
+				return
+			}
 			if num := copy(ram[0x4000:0x8000], RomData[0x4000 * uint32(romBank):0x4000 * (uint32(romBank) + 1)]); num != 0x4000{
 				fmt.Printf("ERRO no bank, copiados %d\n", num)
 				return

diff --git a/gameboygo/video.go b/gameboygo/video.go
@@ -266,11 +266,12 @@ func DrawLine(renderer *sdl.Renderer) {
 					//X flip (0=Normal, 1=Horizontally mirrored)
 					bit = (^Xpixel) & 0x07
 				}
-				color := getPixelColor(data0, data1, bit, palette)
-				if color == WHITE{
-					//the white color in sprites is transparent
+				colorCode := getSpritePixelColor(data0, data1, bit)
+				if colorCode == 0{
+					//the color 0 in sprites is transparent
 					continue
 				}
+				color := getColor(colorCode, palette)
 				if (int(spriteX) + int((^Xpixel)&0x07)) >= 160 {
 					continue
 				}
@@ -284,6 +285,14 @@ func DrawLine(renderer *sdl.Renderer) {
 	}
 }
 
+func getSpritePixelColor(lower, upper, bitNum uint8) uint8{
+	var mask uint8 = (1 << bitNum)
+	if bitNum < 2 {
+		return ((upper & mask) << (1-bitNum)) | ((lower & mask) >> bitNum)
+	}
+	return (upper & mask) >> (bitNum - 1) | ((lower & mask) >> bitNum)
+}
+
 func getPixelColor(lower, upper, bitNum uint8, palette uint8) uint8{
 	var mask uint8 = (1 << bitNum)
 	if bitNum < 2 {