void Slice::Draw(Ray ray, Vector pos, Vector dir, const Level& level, const ResourceCache& res)
{
const int wall_height = std::abs(int(mSurface->h / ray.GetDistance()));
int wall_start = (mSurface->h / 2) - (wall_height / 2);
int wall_end = (mSurface->h / 2) + (wall_height / 2);
if (wall_start < 0) {
wall_start = 0;
}
if (wall_end >= mSurface->h) {
wall_end = mSurface->h - 1;
}
// Get the texture that matches the cell type.
const auto cell_id = level.mGrid[ray.GetMapIntersectionX()][ray.GetMapIntersectionY()] - 1;
//const auto cell_id = level.mGrid[ray.GetMapIntersectionX()][ray.GetMapIntersectionY()] - 1;
const auto wall_tex = res.GetWall(cell_id);
// Where exactly the wall was hit.
double wall_x = ray.GetIntersection().GetY();
wall_x -= std::floor(wall_x);
// X-coordinate on the texture.
int tex_x = wall_x * wall_tex->w;
if (( ray.VerticalSideHit() && dir.GetY() < 0) ||
(!ray.VerticalSideHit() && dir.GetX() > 0))
{
tex_x = wall_tex->w - tex_x - 1;
}
for (int y = wall_start; y < wall_end; y++)
{
const int tex_y = (y * 2 - mSurface->h + wall_height) *
(wall_tex->h / 2) / wall_height;
const auto tex_offset = (wall_tex->pitch * tex_y) + (tex_x * 4);
const auto tex_ptr = static_cast<Uint8*>(wall_tex->pixels) + tex_offset;
SDL_Color color = { tex_ptr[0], tex_ptr[1], tex_ptr[2] };
if (ray.VerticalSideHit())
{
// Give X and Y-sides different brightness.
color.r /= 2;
color.g /= 2;
color.b /= 2;
}
const auto scr_offset = (mSurface->pitch * y) + (mXCoordinate * 4);
const auto scr_ptr = static_cast<Uint8*>(mSurface->pixels) + scr_offset;
memcpy(scr_ptr, &color, sizeof(color));
}
// Get the texture for the ceiling and floor.
// const auto ceiling_tex = res.GetCeiling(0);
const auto floor_tex = res.GetWall(2);
// Position of the floor at the bottom of the wall.
double floor_x_wall;
double floor_y_wall;
if (!ray.VerticalSideHit() && (dir.GetX() > 0)) {
floor_x_wall = ray.GetMapIntersectionX();
floor_y_wall = ray.GetMapIntersectionY() + wall_x;
}
else if (!ray.VerticalSideHit() && (dir.GetX() < 0)) {
floor_x_wall = ray.GetMapIntersectionX() + 1.;
floor_y_wall = ray.GetMapIntersectionY() + wall_x;
}
else if (ray.VerticalSideHit() && (dir.GetY() > 0)) {
floor_x_wall = ray.GetMapIntersectionX() + wall_x;
floor_y_wall = ray.GetMapIntersectionY();
}
else {
floor_x_wall = ray.GetMapIntersectionX() + wall_x;
floor_y_wall = ray.GetMapIntersectionY() + 1.;
}
const double dist_wall = ray.GetDistance();
const double dist_player = .0;
// Draw the floor from below the wall to the bottom of the screen.
for (int y = wall_end; y < mSurface->h; y++)
{
const double cur_dist = mSurface->h / (2. * y - mSurface->h);
const double weight = (cur_dist - dist_player) / (dist_wall - dist_player);
double cur_floor_x = weight * floor_x_wall + (1.0 - weight) * pos.GetX();
double cur_floor_y = weight * floor_y_wall + (1.0 - weight) * pos.GetY();
if (cur_floor_x < 0.) { cur_floor_x = 0.; }
if (cur_floor_y < 0.) { cur_floor_y = 0.; }
const int floor_tex_x = int(cur_floor_x * floor_tex->w / 4) % floor_tex->w;
const int floor_tex_y = int(cur_floor_y * floor_tex->h / 4) % floor_tex->h;
// const auto ceiling_tex_offset = (ceiling_tex->pitch * floor_tex_y) + (floor_tex_x * 4);
// const auto ceiling_tex_ptr = static_cast<Uint8*>(ceiling_tex->pixels) + ceiling_tex_offset;
const auto floor_tex_offset = (floor_tex->pitch * floor_tex_y) + (floor_tex_x * 4);
const auto floor_tex_ptr = static_cast<Uint8*>(floor_tex->pixels) + floor_tex_offset;
// const SDL_Color ceiling_color = { ceiling_tex_ptr[0], ceiling_tex_ptr[1], ceiling_tex_ptr[2] };
SDL_Color floor_color = { floor_tex_ptr[0], floor_tex_ptr[1], floor_tex_ptr[2] };
// Make the floor darker.
floor_color.r /= 2;
floor_color.g /= 2;
floor_color.b /= 2;
// const auto ceiling_offset = (mSurface->pitch * (mSurface->h - y - 1)) + (mXCoordinate * 4);
// const auto ceiling_ptr = static_cast<Uint8*>(mSurface->pixels) + ceiling_offset;
// memcpy(ceiling_ptr, &ceiling_color, sizeof(ceiling_color));
const auto floor_offset = (mSurface->pitch * y) + (mXCoordinate * 4);
const auto floor_ptr = static_cast<Uint8*>(mSurface->pixels) + floor_offset;
memcpy(floor_ptr, &floor_color, sizeof(floor_color));
}
}
