screen.c

#include "screen.h"
#include "cpu.h"

#include <SDL2/SDL.h>

struct nk_color byte_to_color(uint8_t b)
{
	struct nk_color c;
	c.r = (b >> 5) * (255 / 0b111);
	c.g = ((b >> 2) & 0b111) * (255 / 0b111);
	c.b = (b & 0b11) * (255 / 0b11);
	c.a = 255;
	return c;
}

void screen(struct nk_context *ctx, uint8_t *mem, uint8_t size)
{
	struct nk_command_buffer *out = nk_window_get_canvas(ctx);

	struct nk_rect bounds;
	enum nk_widget_layout_states state = nk_widget(&bounds, ctx);

	if (!state)
		return;

	//nk_fill_rect(out, bounds, 0, nk_rgb(255, 0, 0));

	//return;

	for (int i = 0; i < CPU_FB_H; i++)
	{
		for (int j = 0; j < CPU_FB_W; j++)
		{
			nk_fill_rect(out,
				nk_rect(bounds.x + i * size, bounds.y + j * size,
					size, size), 0.0f,
				byte_to_color(mem[i + CPU_FB_H * j]));
		}
	}
}

sdl_screen_t new_sdl_screen(uint8_t size)
{
	sdl_screen_t scr;
	scr.win = SDL_CreateWindow("6502",
		SDL_WINDOWPOS_CENTERED,
		SDL_WINDOWPOS_CENTERED,
		size * 32,
		size * 32,
		0);
	scr.size = size;
	scr.r = SDL_CreateRenderer(scr.win, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);

	return scr;
}

void sdl_screen(sdl_screen_t *scr, uint8_t *mem)
{
	SDL_RenderClear(scr->r);

	SDL_Event e;

	while (SDL_PollEvent(&e))
	{
		switch (e.type)
		{
			case SDL_QUIT:
				exit(0);
		}
	}

	for (int i = 0; i < CPU_FB_H; i++)
	{
		for (int j = 0; j < CPU_FB_W; j++)
		{
			SDL_Rect r =
			{
				i * scr->size,
				j * scr->size,
				scr->size,
				scr->size,
			};

			struct nk_color c = byte_to_color(mem[i + CPU_FB_H * j]);

			SDL_SetRenderDrawColor(scr->r, c.r, c.g, c.b, c.a);
			SDL_RenderFillRect(scr->r, &r);
		}
	}

	SDL_RenderPresent(scr->r);	
}