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Now have a basic sprite system that uses SFML's sprites, but the algorithm for determining how much of a sprite to display is wrong. Need to use the alternate algorithm from LODE's tutorial that draws sprites after rendering.

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Zed A. Shaw 2025-01-23 02:42:43 -05:00
parent 024d5b30e1
commit da7075864b
6 changed files with 38 additions and 36 deletions
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61
raycaster.cpp
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@ -17,7 +17,7 @@ union ColorConv {
};
inline uint32_t dumb_lighting(uint32_t pixel, double distance) {
if(distance < 1) return pixel;
if(distance < 1.0) return pixel;
ColorConv conv{.as_int=pixel};
conv.as_color.r /= distance;
@ -84,7 +84,8 @@ void Raycaster::sprite_casting() {
for(int i = 0; i < $textures.NUM_SPRITES; i++) {
int sprite_index = spriteOrder[i];
Sprite& sprite_rec = $textures.get_sprite(sprite_index);
auto& sprite_texture = $textures.get_texture(sprite_rec.texture);
// auto& sprite_texture = $textures.get_texture(sprite_rec.texture);
sf::Sprite *sf_sprite = sprite_rec.sprite;
double spriteX = sprite_rec.x - $posX;
double spriteY = sprite_rec.y - $posY;
@ -103,18 +104,10 @@ void Raycaster::sprite_casting() {
int spriteScreenX = int(($width / 2) * (1 + transformX / transformY));
int vMoveScreen = int(sprite_rec.elevation * -1 / transformY);
// calculate the height of the sprite on screen
//using "transformY" instead of the real distance prevents fisheye
int spriteHeight = abs(int($height / transformY)) / sprite_rec.vDiv;
//calculate lowest and highest pixel to fill in current stripe
int drawStartY = -spriteHeight / 2 + $height / 2 + vMoveScreen;
if(drawStartY < 0) drawStartY = 0;
int drawEndY = spriteHeight / 2 + $height / 2 + vMoveScreen;
if(drawEndY >= $height) drawEndY = $height - 1;
// calculate width the the sprite
// same as height of sprite, given that it's square
int spriteWidth = abs(int($height / transformY)) / sprite_rec.uDiv;
@ -123,29 +116,29 @@ void Raycaster::sprite_casting() {
int drawEndX = spriteWidth / 2 + spriteScreenX;
if(drawEndX > $width) drawEndX = $width;
//loop through every vertical stripe of the sprite on screen
for(int stripe = drawStartX; stripe < drawEndX; stripe++) {
int texX = int(256 * (stripe - (-spriteWidth / 2 + spriteScreenX)) * textureWidth / spriteWidth) / 256;
// the conditions in the if are:
// 1) it's in front of the camera plane so you don't see things behind you
// 2) ZBuffer, with perpendicular distance
if(transformY > 0 && transformY < ZBuffer[stripe]) {
for(int y = drawStartY; y < drawEndY; y++) {
//256 and 128 factors to avoid floats
int d = (y - vMoveScreen) * 256 - $height * 128 + spriteHeight * 128;
int texY = ((d * textureHeight) / spriteHeight) / 256;
//get current color from the texture
// BUG: this crashes sometimes when the math goes out of bounds
int index = textureWidth * texY + texX;
if(index < 0 || (size_t)index >= sprite_texture.size()) continue;
uint32_t color = sprite_texture[index];
// poor person's transparency, get current color from the texture
if((color & 0x00FFFFFF) != 0) {
RGBA pixel = color;
$pixels[pixcoord(stripe, y)] = pixel;
}
}
}
if(drawStartX < drawEndX && transformY > 0 && transformY < ZBuffer[drawStartX]) {
int vMoveScreen = int(sprite_rec.elevation * -1 / transformY);
//calculate lowest and highest pixel to fill in current stripe
int drawStartY = -spriteHeight / 2 + $height / 2 + vMoveScreen;
if(drawStartY < 0) drawStartY = 0;
int drawEndY = spriteHeight / 2 + $height / 2 + vMoveScreen;
if(drawEndY >= $height) drawEndY = $height - 1;
float x = float(drawStartX + RAY_VIEW_X);
float y = float(drawStartY + RAY_VIEW_Y);
float sprite_w = float(spriteWidth) / float(textureWidth);
float sprite_h = float(spriteHeight) / float(textureHeight);
int texX = int(256 * (drawStartX - (-spriteWidth / 2 + spriteScreenX)) * textureWidth / spriteWidth) / 256;
int texX_end = int(256 * (drawEndX - (-spriteWidth / 2 + spriteScreenX)) * textureWidth / spriteWidth) / 256;
int d = (y - vMoveScreen) * 256 - $height * 128 + spriteHeight * 128;
int texY = ((d * textureHeight) / spriteHeight) / 256;
sf_sprite->setScale({sprite_h, sprite_w});
sf_sprite->setTextureRect(sf::IntRect({texX, texY}, {texX_end, textureHeight}));
sf_sprite->setPosition({x, y});
$window.draw(*sf_sprite);
}
}
}
@ -328,8 +321,8 @@ void Raycaster::draw_ceiling_floor() {
void Raycaster::render() {
draw_ceiling_floor();
cast_rays();
sprite_casting();
draw_pixel_buffer();
sprite_casting();
}
bool Raycaster::empty_space(int new_x, int new_y) {