perf: add condition for updating the screen for slight GPU performanc…

…e improvement
Natan822 · Sep 24, 2024 · f3a9308 · f3a9308
1 parent 62b27db
commit f3a9308
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Showing 3 changed files with 11 additions and 1 deletion.
diff --git a/Chip8Emulator/src/Chip8.cpp b/Chip8Emulator/src/Chip8.cpp
@@ -1,6 +1,8 @@
 #include "Chip8.h"
 #include <fstream>
 
+bool screenUpdate = true;
+
 Chip8::Chip8() 
 	: randGen(std::chrono::system_clock::now().time_since_epoch().count()) 
 {
@@ -331,6 +333,8 @@ void Chip8::OP_CXNN() {
 }
 
 void Chip8::OP_DXYN() {
+	screenUpdate = true;
+
 	uint8_t Vx = (opcode & 0x0F00u) >> 8u;
 	uint8_t Vy = (opcode & 0x00F0u) >> 4u;
 	uint8_t height = opcode & 0xFu;

diff --git a/Chip8Emulator/src/Chip8.h b/Chip8Emulator/src/Chip8.h
@@ -12,6 +12,8 @@ const unsigned int FONTSET_SIZE = 80;
 const unsigned int VIDEO_WIDTH = 64;
 const unsigned int VIDEO_HEIGHT = 32;
 
+extern bool screenUpdate;
+
 class Chip8
 {
 

diff --git a/Chip8Emulator/src/Main.cpp b/Chip8Emulator/src/Main.cpp
@@ -88,7 +88,11 @@ int main(int argc, char* argv[]) {
 		{
 			lastCycleTime = currentCycleTime;
 			chip8.Cycle();
-			update(chip8.video, videoPitch);
+			if (screenUpdate)
+			{
+				update(chip8.video, videoPitch);
+				screenUpdate = false;
+			}
 		}
 	}
 	shutdown();