shithub: m8c

ref: 3b7fcf9811cb02854e815d01cd4aa599407529e6
dir: /render.c/

#include "render.h"

#include "command.h"

#include <SDL2/SDL.h>
#include <SDL2/SDL_blendmode.h>
#include <SDL2/SDL_joystick.h>
#include <SDL2/SDL_mouse.h>
#include <SDL2/SDL_pixels.h>
#include <SDL2/SDL_rect.h>
#include <SDL2/SDL_render.h>
#include <SDL2/SDL_surface.h>
#include <SDL2/SDL_timer.h>
#include <SDL2/SDL_ttf.h>
#include <SDL2/SDL_video.h>
#include <bits/stdint-intn.h>
#include <stdio.h>

SDL_Window *win;
SDL_Renderer *rend;
TTF_Font *font;
SDL_Texture *glyph_texture;
SDL_Texture *background;
SDL_Surface *surface;
static uint32_t ticks;
static uint32_t ticks_fps;
int updates;
int fps;
const int font_size = 8;
uint8_t fullscreen = 0;

// Initializes SDL and creates a renderer and required surfaces
int initialize_sdl() {

  ticks = SDL_GetTicks();

  const int windowWidth = 640;  // SDL window width
  const int windowHeight = 480; // SDL window height

  // retutns zero on success else non-zero
  if (SDL_Init(SDL_INIT_EVERYTHING) != 0) {
    fprintf(stderr, "SDL_Init: %s\n", SDL_GetError());
    return -1;
  }

  if (TTF_Init() == -1) {
    printf("TTF_Init: %s\n", TTF_GetError());
    return -1;
  }

  win = SDL_CreateWindow("m8c", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED,
                         windowWidth, windowHeight,
                         SDL_WINDOW_SHOWN | SDL_WINDOW_OPENGL |
                             SDL_WINDOW_RESIZABLE);

  rend = SDL_CreateRenderer(win, -1, SDL_RENDERER_ACCELERATED);

  font = TTF_OpenFont("stealth57.ttf", font_size);

  surface = SDL_CreateRGBSurfaceWithFormat(0, 320, 240, 8,
                                           SDL_PIXELFORMAT_ARGB8888);
  if (surface == NULL) {
    SDL_Log("SDL_CreateRGBSurfaceWithFormat() failed: %s", SDL_GetError());
    exit(1);
  }

  SDL_SetRenderTarget(rend, background);

  return 1;
}

void close_renderer() {
  SDL_FreeSurface(surface);
  SDL_DestroyTexture(glyph_texture);
  SDL_DestroyTexture(background);
  TTF_CloseFont(font);
  SDL_DestroyRenderer(rend);
  SDL_DestroyWindow(win);
}

void toggle_fullscreen(){
  int fullscreen_state = SDL_GetWindowFlags(win) & SDL_WINDOW_FULLSCREEN;
  SDL_SetWindowFullscreen(win, fullscreen_state ? 0 : SDL_WINDOW_FULLSCREEN);
  SDL_ShowCursor(fullscreen_state);
}

int draw_character(struct draw_character_command *command) {

  SDL_Color fgcolor = {command->foreground.r, command->foreground.g,
                       command->foreground.b};

  SDL_Color bgcolor = {command->background.r, command->background.g,
                       command->background.b};

  SDL_Surface *char_surface;

  // Trash80: yeah I think I did something silly that if both are the same color
  // it means transparent background or something
  if (fgcolor.r == bgcolor.r && fgcolor.g == bgcolor.g &&
      fgcolor.b == bgcolor.b) {
    char_surface = TTF_RenderUTF8_Solid(font, (char *)&command->c, fgcolor);
  } else {
    char_surface =
        TTF_RenderUTF8_Shaded(font, (char *)&command->c, fgcolor, bgcolor);
  }

  if (!char_surface) {
    fprintf(stderr, "TTF_RenderUTF8_Solid error %s\n", TTF_GetError());
    return -1;
  }

  int texW, texH = 0;
  TTF_SizeUTF8(font, (char *)&command->c, &texW, &texH);
  SDL_Rect dstrect = {command->pos.x, command->pos.y + 3, texW, texH};

  SDL_BlitSurface(char_surface,NULL,surface,&dstrect);

  SDL_FreeSurface(char_surface);

  return 1;
}

void draw_rectangle(struct draw_rectangle_command *command) {
  SDL_Rect render_rect;
  render_rect.x = command->pos.x;
  render_rect.y = command->pos.y;
  render_rect.h = command->size.height;
  render_rect.w = command->size.width;

  uint32_t color = SDL_MapRGBA(surface->format, command->color.r, command->color.g, command->color.b, 255);

  SDL_FillRect(surface, &render_rect, color);
}

// Direct pixel writing function by unwind, https://stackoverflow.com/a/20070273 !
void set_pixel(SDL_Surface *surface, int x, int y, Uint32 pixel)
{
  Uint32 * const target_pixel = (Uint32 *) ((Uint8 *) surface->pixels
                                             + y * surface->pitch
                                             + x * surface->format->BytesPerPixel);
  *target_pixel = pixel;
}


void draw_waveform(struct draw_oscilloscope_waveform_command *command) {
  memset(surface->pixels,0,surface->w*20*surface->format->BytesPerPixel); // clear the oscilloscope area
  uint32_t color = SDL_MapRGBA(surface->format, command->color.r, command->color.g, command->color.b, 255); // set oscilloscope color
  for (int i = 0; i < command->waveform_size; i++) {
    set_pixel(surface, i, command->waveform[i], color); //draw the pixels directly to the surface
  }
}

void render_screen() {
  if (SDL_GetTicks() - ticks > 16) {
    ticks = SDL_GetTicks();
    SDL_RenderClear(rend);
    background = SDL_CreateTextureFromSurface(rend, surface);
    SDL_RenderCopy(rend, background, NULL, NULL);
    SDL_RenderPresent(rend);
    SDL_DestroyTexture(background);
    fps++;
    if (SDL_GetTicks() - ticks_fps > 5000) {
      ticks_fps = SDL_GetTicks();
      fprintf(stderr, "%d fps\n", fps / 5);
      fps = 0;
    }
  }
}