fix(graphics): resolve scroll and high resolution issues

gaoliveira21 · Dec 30, 2023 · cb53a63 · cb53a63
1 parent acdd595
commit cb53a63
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Showing 4 changed files with 4 additions and 4 deletions.
diff --git a/cli/roms/test/Test128.ch8 b/cli/roms/test/Test128.ch8
diff --git a/cli/roms/test/scroll.ch8 b/cli/roms/test/scroll.ch8
diff --git a/cli/roms/test/scroll2.ch8 b/cli/roms/test/scroll2.ch8
diff --git a/core/cpu/cpu.go b/core/cpu/cpu.go
@@ -80,9 +80,9 @@ func (cpu *CPU) clock() {
 
 	switch opcode.instruction {
 	case 0x0000:
-		switch opcode.registerY {
-		case 0xC:
+		if opcode.registerY == 0xC {
 			cpu.scd(opcode.n)
+			return
 		}
 
 		switch opcode.nnn {
@@ -330,8 +330,8 @@ func (cpu *CPU) ldm(vIndex uint8) {
 }
 
 func (cpu *CPU) drw(oc *opcode) {
-	x := cpu.v[oc.registerX] & 0x3F
-	y := cpu.v[oc.registerY] & 0x1F
+	x := cpu.v[oc.registerX] & (byte(cpu.Graphics.Width - 1))
+	y := cpu.v[oc.registerY] & (byte(cpu.Graphics.Height - 1))
 	cpu.v[0xF] = 0x00
 
 	for i := 0; uint8(i) < oc.n; i++ {