NESmerize/gui.cpp at master · njaladan/NESmerize · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
// TODO: think about apu communication with gui?

class GUI {
  public:
  PPU* ppu;
  Memory* memory;
  SDL_Window* window;
  SDL_Renderer* renderer;
  SDL_Texture* texture;
  SDL_Rect baselayer;
  bool valid;
  int frames;

  void set_ppu(PPU*);
  void initialize();
  void close_gui();
  void render_frame(uint8_t*);
  uint8_t get_input();
};

struct InputData {
  bool a : 1;
  bool b : 1;
  bool select : 1;
  bool start : 1;
  bool up : 1;
  bool down : 1;
  bool left : 1;
  bool right : 1;
};

union Input {
  uint8_t value;
  InputData data;
};

void GUI::initialize() {
  SDL_Init(SDL_INIT_VIDEO || SDL_INIT_AUDIO);
	// Create window
	window = SDL_CreateWindow(
    "NESmerize",
    SDL_WINDOWPOS_UNDEFINED,
    SDL_WINDOWPOS_UNDEFINED,
    256,
    240,
    SDL_WINDOW_RESIZABLE
  );
  renderer = SDL_CreateRenderer(
    window,
    -1,
    SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC
  );
  SDL_RenderSetLogicalSize(renderer, 256, 240);
  SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_BLEND);
  texture = SDL_CreateTexture(
    renderer,
    SDL_PIXELFORMAT_ARGB8888,
    SDL_TEXTUREACCESS_STREAMING,
    256,
    240
  );
  if (texture == NULL) {
    exit(1);
  }
  baselayer = {
    0,
    0,
    256,
    240
  };
  valid = true;
  frames = 0;
}

void GUI::close_gui() {
	// Destroy window
	SDL_DestroyRenderer(renderer);
	SDL_DestroyWindow(window);

	// Quit SDL subsystems
	IMG_Quit();
	SDL_Quit();
  valid = false;
}

uint8_t GUI::get_input() {
  Input input_data;
  input_data.value = 0;
  SDL_PumpEvents(); // update event queue to avoid being a frame behind
  const uint8_t* keystate = SDL_GetKeyboardState(NULL);

  // update bitfield with information about keyboard
  if (keystate[SDL_SCANCODE_DOWN]) {
    input_data.data.down = 1;
  }
  if (keystate[SDL_SCANCODE_UP]) {
    input_data.data.up = 1;
  }
  if (keystate[SDL_SCANCODE_RIGHT]) {
    input_data.data.right = 1;
  }
  if (keystate[SDL_SCANCODE_LEFT]) {
    input_data.data.left = 1;
  }
  if (keystate[SDL_SCANCODE_Z]) {
    input_data.data.a = 1;
  }
  if (keystate[SDL_SCANCODE_X]) {
    input_data.data.b = 1;
  }
  if (keystate[SDL_SCANCODE_RSHIFT]) {
    input_data.data.select = 1;
  }
  if (keystate[SDL_SCANCODE_RETURN]) {
    input_data.data.start = 1;
  }

  return input_data.value;
}

// TODO: why does this work at 60fps even without vsync or anything?
void GUI::render_frame(uint8_t* framebuffer) {
	SDL_Event e;

	while (SDL_PollEvent(&e) != 0) {
		if (e.type == SDL_QUIT) {
      close_gui();
			return;
		}
	}
  // update with new frame data
  SDL_UpdateTexture(texture, nullptr, framebuffer, 256 * 4);
  SDL_SetRenderDrawColor(renderer, 0, 0, 0, 0xff);
  SDL_RenderClear(renderer);
  SDL_RenderCopy(renderer, texture, nullptr, nullptr);
	SDL_RenderPresent(renderer);
  frames++;
}