[cpp] screenshot support

cpp/src/args.cpp

@@ -13,6 +13,7 @@ Args::Args(int argc, char *argv[]) {
     args::Flag debug_ram(parser, "debug-ram", "Debug RAM", {'a', "debug-ram"});
     args::ValueFlag<int> frames(parser, "frames", "Exit after N frames", {'f', "frames"});
     args::ValueFlag<int> profile(parser, "profile", "Exit after N seconds", {'p', "profile"});
+    args::ValueFlag<std::string> screenshot(parser, "screenshot", "Write a BMP to this file on exit", {'s', "screenshot"});
     args::Flag turbo(parser, "turbo", "No sleep between frames", {'t', "turbo"});
     args::Flag version(parser, "version", "Show build info", {'v', "version"});
     args::Positional<std::string> rom(parser, "rom", "Path to a .gb file");
@@ -48,6 +49,7 @@ Args::Args(int argc, char *argv[]) {
     this->debug_ram = debug_ram;
     this->frames = frames ? args::get(frames) : 0;
     this->profile = profile ? args::get(profile) : 0;
+    this->screenshot = screenshot ? args::get(screenshot) : "";
     this->turbo = turbo;
     this->rom = args::get(rom);
 }

cpp/src/args.h

@@ -15,6 +15,7 @@ class Args {
     bool debug_ram;
     int frames;
     int profile;
+    std::string screenshot;
     bool turbo;
     std::string rom;
 };

cpp/src/gameboy.cpp

@@ -4,7 +4,7 @@ GameBoy::GameBoy(Args *args) {
     this->cart = new Cart(args->rom);
     this->ram = new RAM(this->cart, args->debug_ram);
     this->cpu = new CPU(this->ram, args->debug_cpu);
-    this->gpu = new GPU(this->cpu, cart->name, args->headless, args->debug_gpu);
+    this->gpu = new GPU(this->cpu, cart->name, args->screenshot, args->headless, args->debug_gpu);
     this->buttons = new Buttons(this->cpu, args->headless);
     if(!args->silent) new APU(this->cpu, args->debug_apu);
     this->clock = new Clock(this->buttons, args->frames, args->profile, args->turbo);

cpp/src/gpu.cpp

@@ -18,7 +18,8 @@ u32 bmask = 0x00ff0000;
 u32 amask = 0xff000000;
 #endif
 
-GPU::GPU(CPU *cpu, char *title, bool headless, bool debug) {
+GPU::GPU(CPU *cpu, char *title, std::string screenshot, bool headless, bool debug) {
+    this->screenshot = screenshot;
     this->cpu = cpu;
     this->debug = debug;
 
@@ -62,6 +63,10 @@ GPU::GPU(CPU *cpu, char *title, bool headless, bool debug) {
 };
 
 GPU::~GPU() {
+    std::cout << "Screenshot " << this->screenshot << "\n";
+    if(this->screenshot.length() > 0) {
+        SDL_SaveBMP(this->buffer, this->screenshot.c_str());
+    }
     SDL_FreeSurface(this->buffer);
     if(this->hw_window) SDL_DestroyWindow(this->hw_window);
     SDL_Quit();
@@ -355,4 +360,4 @@ SDL_Color gen_hue(u8 n) {
     }
 }
 
-bool Sprite::is_live() { return x > 0 && x < 168 && y > 0 && y < 160; }
+bool Sprite::is_live() { return x > 0 && x < 168 && y > 0 && y < 160; }

cpp/src/gpu.h

@@ -51,6 +51,7 @@ struct Sprite {
 class GPU {
 private:
     bool debug;
+    std::string screenshot;
     SDL_Window *hw_window;
     SDL_Texture *hw_buffer;
     SDL_Renderer *hw_renderer;
@@ -62,7 +63,7 @@ class GPU {
     CPU *cpu;
 
 public:
-    GPU(CPU *cpu, char *title, bool headless, bool debug);
+    GPU(CPU *cpu, char *title, std::string screenshot, bool headless, bool debug);
     ~GPU();
     void tick();