Small ppu fixes

.gitignore

@@ -1,3 +1,4 @@
 cmake-build-debug/
 .idea/
 .vs/
+out/

CMakeLists.txt

@@ -3,6 +3,8 @@ project(nes)
 
 set(CMAKE_CXX_STANDARD 23)
 
+add_compile_definitions(SDL_MAIN_HANDLED)
+
 add_executable(nes
         main.cpp
         src/Cartridge.cpp

CMakePresets.json

@@ -0,0 +1,59 @@
+{
+	"version": 3,
+	"configurePresets": [
+		{
+			"name": "windows-base",
+			"description": "Target Windows with the Visual Studio development environment.",
+			"hidden": true,
+			"generator": "Ninja",
+			"binaryDir": "${sourceDir}/out/build/${presetName}",
+			"installDir": "${sourceDir}/out/install/${presetName}",
+			"cacheVariables": {
+				"CMAKE_C_COMPILER": "cl.exe",
+				"CMAKE_CXX_COMPILER": "cl.exe"
+			},
+			"condition": {
+				"type": "equals",
+				"lhs": "${hostSystemName}",
+				"rhs": "Windows"
+			},
+			"toolchainFile": "$env{VCPKG_ROOT}/scripts/buildsystems/vcpkg.cmake"
+		},
+		{
+			"name": "x64-debug",
+			"displayName": "x64 Debug",
+			"description": "Target Windows (64-bit) with the Visual Studio development environment. (Debug)",
+			"inherits": "windows-base",
+			"architecture": {
+				"value": "x64",
+				"strategy": "external"
+			},
+			"cacheVariables": { "CMAKE_BUILD_TYPE": "Debug" }
+		},
+		{
+			"name": "x64-release",
+			"displayName": "x64 Release",
+			"description": "Target Windows (64-bit) with the Visual Studio development environment. (RelWithDebInfo)",
+			"inherits": "x64-debug",
+			"cacheVariables": { "CMAKE_BUILD_TYPE": "Release" }
+		},
+		{
+			"name": "x86-debug",
+			"displayName": "x86 Debug",
+			"description": "Target Windows (32-bit) with the Visual Studio development environment. (Debug)",
+			"inherits": "windows-base",
+			"architecture": {
+				"value": "x86",
+				"strategy": "external"
+			},
+			"cacheVariables": { "CMAKE_BUILD_TYPE": "Debug" }
+		},
+		{
+			"name": "x86-release",
+			"displayName": "x86 Release",
+			"description": "Target Windows (32-bit) with the Visual Studio development environment. (RelWithDebInfo)",
+			"inherits": "x86-debug",
+			"cacheVariables": { "CMAKE_BUILD_TYPE": "Release" }
+		}
+	]
+}

main.cpp

@@ -13,7 +13,8 @@ int main() {
     nes::SdlWindow window(nes::Ppu::SCREEN_WIDTH, nes::Ppu::SCREEN_HEIGHT);
 
     device.setNewFrameCallback(std::bind(&nes::SdlWindow::drawFrame, &window, _1));
-    device.insertCartridge("/home/selim/Downloads/nestest.nes");
+    //device.insertCartridge("/home/selim/Downloads/nestest.nes");
+    device.insertCartridge("C:\\Users\\selim\\Documents\\nestest.nes");
 
     uint64_t cycles = 0;
     while (cycles < 1000000000) {

src/Bus.cpp

@@ -32,7 +32,6 @@ namespace nes {
             _ram[address & 0x07FF] = value;
         }
         else if(address >= 0x2000 && address < 0x4000) {
-            std::cout << "PPU write at address: " << address << std::endl;
             _ppu->write(address & 0x0007, value);
         }
         else if(address >= 0x8000) {

src/Ppu.cpp

@@ -4,6 +4,8 @@
 
 #include "Ppu.h"
 
+#include <iostream>
+
 namespace nes {
 
     Ppu::Ppu(): _column{}, _scanline{}, _status{}, _control{}, _mask{} {
@@ -84,6 +86,20 @@ namespace nes {
             _status.verticalBlank = 1;
         }
 
+        // All visible scanlines
+        if (_scanline >= -1 && _scanline < 240) {
+            if (_scanline == -1 && _column == 1) {
+                _status.verticalBlank = 0;
+            }
+
+            //
+            if ((_column >= 2 && _column < 258) || (_column >= 321 && _column < 338)) {
+                switch ((_column - 1) % 8) {
+
+                }
+            }
+        }
+
         uint8_t colorIndex = 0;
         uint8_t palette = 0;
 
@@ -119,6 +135,7 @@ namespace nes {
             case Status:
                 value = _status.value & 0xE0;
                 _status.verticalBlank = 0;
+                _addressWriteInProgress = false;
                 break;
             case PpuData:
                 value = _dataTemp;
@@ -126,7 +143,7 @@ namespace nes {
                 if(address >= 0x3F00) {
                     value = _dataTemp;
                 }
-                _vRamAddress += _control.incrementMode ? 32 : 1;
+                _vRamAddress.value += _control.incrementMode ? 32 : 1;
                 break;
         }
         return value;
@@ -136,22 +153,35 @@ namespace nes {
         switch (address) {
             case Control:
                 _control.value = value;
+                _tRamAddress.nameTableX = _control.nameTableX;
+                _tRamAddress.nameTableY = _control.nameTableY;
                 break;
             case Mask:
                 _mask.value = value;
                 break;
+            case Scroll:
+                if (_addressWriteInProgress) {
+                    _tRamAddress.fineY = value & 0x7;
+                    _tRamAddress.coarseY = value >> 3;
+                }
+                else {
+                    _fineX = value & 0x7;
+                    _tRamAddress.coarseX = value >> 3;
+                }
+                _addressWriteInProgress = !_addressWriteInProgress;
+                break;
             case PpuAddress:
                 if(_addressWriteInProgress) {
-                    _vRamAddressTemp = (_vRamAddressTemp & 0xFF00) | value;
+                    _tRamAddress.value = (_tRamAddress.value & 0xFF00) | value;
-                    _vRamAddress = _vRamAddressTemp;
+                    _vRamAddress.value = _tRamAddress.value;
                 } else {
-                    _vRamAddressTemp = ((value & 0x3F) << 8) | (_vRamAddressTemp & 0x00FF);
+                    _tRamAddress.value = ((value & 0x3F) << 8) | (_tRamAddress.value & 0x00FF);
                 }
                 _addressWriteInProgress = !_addressWriteInProgress;
                 break;
             case PpuData:
-                internalWrite(_vRamAddress, value);
+                internalWrite(_vRamAddress.value, value);
-                _vRamAddress += _control.incrementMode ? 32 : 1;
+                _vRamAddress.value += _control.incrementMode ? 32 : 1;
                 break;
             default:
                 break;
@@ -177,7 +207,7 @@ namespace nes {
             address &= 0x03FF;
             return _nameTable[address];
         }
-        else if(address >= 0x3F00 && address < 0x4000) {
+        else if(address >= 0x3F00 && address <   0x4000) {
             address &= 0x1F;
             if (address == 0x0010) address = 0x0000;
             if (address == 0x0014) address = 0x0004;
@@ -197,6 +227,7 @@ namespace nes {
         }
         else if(address >= 0x2000 && address < 0x3F00) {
             address &= 0x03FF;
+            //std::cout << std::hex << "Writing nametable, address: " << (int)address << ", value: " << (int)value << std::endl;
             _nameTable[address] = value;
         }
         else if(address >= 0x3F00 && address < 0x4000) {

src/Ppu.h

@@ -74,6 +74,18 @@ namespace nes {
             uint8_t value;
         };
 
+        union LoopyRegister {
+            struct {
+                uint8_t coarseX : 5;
+                uint8_t coarseY : 5;
+                uint8_t nameTableX : 1;
+                uint8_t nameTableY : 1;
+                uint8_t fineY : 3;
+                uint8_t unused : 1;
+            };
+            uint16_t value;
+        };
+
     public:
         Ppu();
         bool tick();
@@ -97,10 +109,11 @@ namespace nes {
         ControlRegister _control;
         MaskRegister _mask;
 
-        uint16_t _vRamAddress;
+        LoopyRegister _vRamAddress;
-        uint16_t _vRamAddressTemp;
+        LoopyRegister _tRamAddress;
         bool _addressWriteInProgress;
         uint8_t _dataTemp;
+        uint8_t _fineX;
 
     private:
         std::unique_ptr<uint8_t[]> _nameTable;