Adding PPU stub class

CMakeLists.txt

@@ -16,7 +16,7 @@ add_executable(nes
         src/Mapper/Mapper.cpp
         src/Mapper/Mapper.h
         src/Mapper/Mapper0.cpp
-        src/Mapper/Mapper0.h)
+        src/Mapper/Mapper0.h src/Ppu.cpp src/Ppu.h)
 
 find_package(SDL2 CONFIG REQUIRED)
 target_link_libraries(nes PRIVATE SDL2::SDL2)

src/Nes.cpp

@@ -29,7 +29,10 @@ namespace nes {
 
         size_t ticks = 0;
         while (ticks <= 15000) {
+            _ppu->tick();
+            if(ticks % 3 == 0) {
                 _cpu->tick();
+            }
             ticks++;
         }
 

src/Nes.h

@@ -7,6 +7,8 @@
 
 #include "Cpu.h"
 #include "Cartridge.h"
+#include "Ppu.h"
+
 #include <filesystem>
 #include <optional>
 
@@ -22,6 +24,7 @@ namespace nes {
 
     private:
         std::unique_ptr<Cpu> _cpu;
+        std::shared_ptr<Ppu> _ppu;
         std::shared_ptr<Cartridge> _cartridge;
     };
 

src/Ppu.cpp

@@ -0,0 +1,26 @@
+//
+// Created by selim on 8/22/23.
+//
+
+#include "Ppu.h"
+
+namespace nes {
+
+    Ppu::Ppu(): _column{}, _scanline{} {
+
+    }
+
+    void Ppu::tick() {
+
+
+        _column++;
+        if(_column >= 341) {
+            _column = 0;
+            _scanline++;
+
+            if(_scanline >= 261) {
+                _scanline = -1;
+            }
+        }
+    }
+}

src/Ppu.h

@@ -0,0 +1,24 @@
+//
+// Created by selim on 8/22/23.
+//
+
+#ifndef NES_PPU_H
+#define NES_PPU_H
+
+#include <cstdint>
+
+namespace nes {
+
+    class Ppu {
+    public:
+        Ppu();
+        void tick();
+
+    private:
+        int16_t _column;
+        int16_t _scanline;
+    };
+
+}
+
+#endif //NES_PPU_H