示例#1
0
float terrain_height(terrain* ter, vec2 position) {
  
  vec2 amount = vec2_fmod(position, 1.0);
  
  vec2 top_left = vec2_new(floor(position.x), floor(position.y));
  vec2 top_right = vec2_new(ceil(position.x), floor(position.y));
  vec2 bot_left = vec2_new(floor(position.x), ceil(position.y));
  vec2 bot_right = vec2_new(ceil(position.x), ceil(position.y));
  
  top_left.x = clamp(top_left.x, 0, ter->width-1);
  top_left.y = clamp(top_left.y, 0, ter->height-1);
  top_right.x = clamp(top_right.x, 0, ter->width-1);
  top_right.y = clamp(top_right.y, 0, ter->height-1);
  bot_left.x = clamp(bot_left.x, 0, ter->width-1);
  bot_left.y = clamp(bot_left.y, 0, ter->height-1);
  bot_right.x = clamp(bot_right.x, 0, ter->width-1);
  bot_right.y = clamp(bot_right.y, 0, ter->height-1);
  
  float s0 = ter->heightmap[(int)top_left.x + (int)top_left.y * ter->width];
  float s1 = ter->heightmap[(int)top_right.x + (int)top_right.y * ter->width];
  float s2 = ter->heightmap[(int)bot_left.x + (int)bot_left.y * ter->width];
  float s3 = ter->heightmap[(int)bot_right.x + (int)bot_right.y * ter->width];
  
  return bilinear_interp(s1, s0, s3, s2, amount.x, amount.y);
  
}
示例#2
0
文件: noise.c 项目: yanbin-ha/Corange
static float perlin_noise2D(vec2 v) {

    vec2 amount = vec2_fmod(v,1.0);

    vec2 p1 = vec2_floor(v);
    vec2 p2 = vec2_add(p1, vec2_new(1,0) );
    vec2 p3 = vec2_add(p1, vec2_new(0,1) );
    vec2 p4 = vec2_add(p1, vec2_new(1,1) );

    int h1 = vec2_mix_hash(p1);
    int h2 = vec2_mix_hash(p2);
    int h3 = vec2_mix_hash(p3);
    int h4 = vec2_mix_hash(p4);

    double result = bismootherstep_interp(h2, h1, h4, h3, amount.x, amount.y);

    return result / INT_MAX;

}
示例#3
0
static void collision_detection() {
  
  /*
    Collision is fairly simplistic and looks something like this.
    
     @-----@    We check for collision in those points here which
    @       @   are @ signs. If any are colliding with a solid tile
    |       |   then we shift the player so that they are no longer
    @       @   colliding with it. Also invert the velocity.
     @-----@ 
  */
  
  character* main_char = entity_get("main_char");
  
  const float buffer = 4;
  const float bounce = 0.5;
  
  vec2 diff;
  
  /* Bottom Collision */
  
  diff = vec2_fmod(main_char->position, TILE_SIZE);
  
  vec2 bottom1 = vec2_add(main_char->position, vec2_new(buffer, TILE_SIZE));
  vec2 bottom2 = vec2_add(main_char->position, vec2_new(TILE_SIZE - buffer, TILE_SIZE));
  
  bool bottom1_col = tile_has_collision(level_tile_at(current_level, bottom1));
  bool bottom2_col = tile_has_collision(level_tile_at(current_level, bottom2));
  
  if (bottom1_col || bottom2_col) {
    main_char->position = vec2_add(main_char->position, vec2_new(0,-diff.y));
    main_char->velocity.y *= -bounce;
  }
  
  /* Top Collision */
  
  diff = vec2_fmod(main_char->position, TILE_SIZE);
  
  vec2 top1 = vec2_add(main_char->position, vec2_new(buffer, 0));
  vec2 top2 = vec2_add(main_char->position, vec2_new(TILE_SIZE - buffer, 0));
  
  bool top1_col = tile_has_collision(level_tile_at(current_level, top1));
  bool top2_col = tile_has_collision(level_tile_at(current_level, top2));
  
  if (top1_col || top2_col) {
    main_char->position = vec2_add(main_char->position, vec2_new(0, TILE_SIZE - diff.y));
    main_char->velocity.y *= -bounce;
  }
  
  /* Left Collision */
  
  diff = vec2_fmod(main_char->position, TILE_SIZE);
  
  vec2 left1 = vec2_add(main_char->position, vec2_new(0, buffer));
  vec2 left2 = vec2_add(main_char->position, vec2_new(0, TILE_SIZE - buffer));
  
  bool left1_col = tile_has_collision(level_tile_at(current_level, left1));
  bool left2_col = tile_has_collision(level_tile_at(current_level, left2));
  
  if (left1_col || left2_col) {
    main_char->position = vec2_add(main_char->position, vec2_new(TILE_SIZE - diff.x,0));
    main_char->velocity.x *= -bounce;
  }
  
  /* Right Collision */
  
  diff = vec2_fmod(main_char->position, TILE_SIZE);
  
  vec2 right1 = vec2_add(main_char->position, vec2_new(TILE_SIZE, buffer));
  vec2 right2 = vec2_add(main_char->position, vec2_new(TILE_SIZE, TILE_SIZE - buffer));
  
  bool right1_col = tile_has_collision(level_tile_at(current_level, right1));
  bool right2_col = tile_has_collision(level_tile_at(current_level, right2));
  
  if (right1_col || right2_col) {
    main_char->position = vec2_add(main_char->position, vec2_new(-diff.x,0));
    main_char->velocity.x *= -bounce;
  }
  
}