raycaster/v2/raycaster.py

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2023-01-14 10:39:52 +01:00
#!/usr/bin/env python3
# RAYCASTER
# Inspired by https://www.youtube.com/watch?v=gYRrGTC7GtA
#
# pip install pysdl2 pysdl2-dll pypng
import sys
import sdl2.ext
import math
import time
import ctypes
import png
# Map cfg
MAP_HIDDEN = True
MAP_SCALE = 24
MAP_SIZE = 17
MAP_WIN_WIDTH = MAP_SIZE * MAP_SCALE
MAP_WIN_HEIGHT = MAP_SIZE * MAP_SCALE
# Textures cfg
TEXTURES = [
"assets/texture_wall.png",
"assets/texture_wall.png",
"assets/texture_wall.png"
]
TEXTURE_SIZE = 64
# Raycast cfg
RAYCAST_WIN_WIDTH = 1000
RAYCAST_WIN_HEIGHT = 600
RAYCAST_RESOLUTION_SCALING = 4
RAYCAST_RENDER_WIDTH = int(RAYCAST_WIN_WIDTH / RAYCAST_RESOLUTION_SCALING)
RAYCAST_RENDER_HEIGHT = int(RAYCAST_WIN_HEIGHT / RAYCAST_RESOLUTION_SCALING)
DOF = 2*MAP_SIZE # Depth Of Field
CEILING_COLOR = sdl2.ext.Color(0,128,255,255)
FLOOR_COLOR = sdl2.ext.Color(0,128,0,255)
# Player cfg
PLAYER_SPEED = 8
PLAYER_ROTATION_SPEED = 0.1
PLAYER_SPAWN_POSITION = {"x": int(MAP_SCALE * 2), "y": int(MAP_SCALE * 5), "r": 0} # r is rotation in radiants
# Dungeon data
MAP = [
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
2, 2, 2, 2, 2, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
3, 3, 3, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1,
2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 0, 3, 3, 3, 3, 3, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1,
2, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
2, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
]
class Main:
def __init__(self):
# Check valid map
if len(MAP) != MAP_SIZE * MAP_SIZE:
raise ValueError("Map size is {}, but should be a power of {}".format(len(MAP), MAP_SIZE))
# Load textures
self.textures = []
for texFile in TEXTURES:
self.textures.append(self.loadTexture(texFile))
# Graphics
sdl2.ext.init()
if not MAP_HIDDEN:
self.mapWindow = sdl2.ext.Window("2D Map", size=(MAP_WIN_WIDTH, MAP_WIN_HEIGHT))
self.mapWindow.show()
self.mapSurface = self.mapWindow.get_surface()
self.raycastWindow = sdl2.ext.Window("3D View", size=(RAYCAST_WIN_WIDTH, RAYCAST_WIN_HEIGHT))
self.raycastWindow.show()
self.raycastSurface = self.raycastWindow.get_surface()
self.raycast_u32_pixels = ctypes.cast(self.raycastSurface.pixels, ctypes.POINTER(ctypes.c_uint32)) # Raw SDL surface pixel array
# Player
self.player_position = PLAYER_SPAWN_POSITION
return
def run(self):
lastFpsCalcTime = 0
frames = 0
running = True
while running:
events = sdl2.ext.get_events()
for event in events:
if event.type == sdl2.SDL_QUIT or (event.type == sdl2.SDL_KEYDOWN and event.key.keysym.sym == sdl2.SDLK_ESCAPE):
running = False
break
keystate = sdl2.SDL_GetKeyboardState(None)
# Rotate player
if keystate[sdl2.SDL_SCANCODE_LEFT]:
self.player_position["r"] = self.player_position["r"] - PLAYER_ROTATION_SPEED
elif keystate[sdl2.SDL_SCANCODE_RIGHT]:
self.player_position["r"] = self.player_position["r"] + PLAYER_ROTATION_SPEED
# Compute deltax and deltay based on player direction
player_delta_x = math.cos(self.player_position["r"]) * PLAYER_SPEED
player_delta_y = math.sin(self.player_position["r"]) * PLAYER_SPEED
# Move player based on its direction
if keystate[sdl2.SDL_SCANCODE_UP]:
self.movePlayerRelative(player_delta_x, player_delta_y)
elif keystate[sdl2.SDL_SCANCODE_DOWN]:
self.movePlayerRelative(-player_delta_x, -player_delta_y)
# Limit position into dungeon bounds
if self.player_position["x"] < 0:
self.player_position["x"] = 0
if self.player_position["x"] > MAP_WIN_WIDTH:
self.player_position["x"] = MAP_WIN_WIDTH
if self.player_position["y"] < 0:
self.player_position["y"] = 0
if self.player_position["y"] > MAP_WIN_HEIGHT:
self.player_position["y"] = MAP_WIN_HEIGHT
if self.player_position["r"] > 2*math.pi:
self.player_position["r"] = 0
if self.player_position["r"] < 0:
self.player_position["r"] = 2*math.pi
self.draw()
if not MAP_HIDDEN:
self.mapWindow.refresh()
self.raycastWindow.refresh()
# Calculate FPS
frames = frames + 1
if time.time() - lastFpsCalcTime > 1:
fps = frames/(time.time() - lastFpsCalcTime)
print(int(fps))
frames = 0
lastFpsCalcTime = time.time()
return 0
def movePlayerRelative(self, player_delta_x, player_delta_y):
# Prevent player from going into walls (X axis)
newPlayerX = int(self.player_position["x"] + player_delta_x)
mapX = int(newPlayerX / MAP_SCALE)
mapY = int(self.player_position["y"] / MAP_SCALE)
mapArrayPosition = mapY * MAP_SIZE + mapX
if mapArrayPosition >= 0 and mapArrayPosition < MAP_SIZE*MAP_SIZE-1 and MAP[mapArrayPosition] == 0:
# Move player (X)
self.player_position["x"] = newPlayerX
# Prevent player from going into walls (Y axis)
newPlayerY = int(self.player_position["y"] + player_delta_y)
mapX = int(self.player_position["x"] / MAP_SCALE)
mapY = int(newPlayerY / MAP_SCALE)
mapArrayPosition = mapY * MAP_SIZE + mapX
if mapArrayPosition >= 0 and mapArrayPosition < MAP_SIZE*MAP_SIZE-1 and MAP[mapArrayPosition] == 0:
# Move player (Y)
self.player_position["y"] = newPlayerY
def draw(self):
if not MAP_HIDDEN:
self.draw2Dmap()
self.drawPlayer()
self.drawRays()
def drawPlayer(self):
# Player in 2D map
sdl2.ext.draw.fill(self.mapSurface, sdl2.ext.Color(0,255,0,255), (self.player_position["x"] - 2, self.player_position["y"] - 2, 4, 4))
# Player line of sight in 2D map
ray = {
"x": int(self.player_position["x"] + math.cos(self.player_position["r"]) * 50), # deltaX + playerX
"y": int(self.player_position["y"] + math.sin(self.player_position["r"]) * 50) # deltaY + playerY
}
sdl2.ext.draw.line(self.mapSurface, sdl2.ext.Color(255,0,0,255), (self.player_position["x"], self.player_position["y"], ray["x"], ray["y"]))
def draw2Dmap(self):
# 2D map
sdl2.ext.draw.fill(self.mapSurface, sdl2.ext.Color(0,0,0,255)) # Clears map screen
for i in range(len(MAP)):
posX = i % MAP_SIZE * MAP_SCALE
posY = math.floor(i / MAP_SIZE) * MAP_SCALE
color = 0
if MAP[i] > 0:
color = 255
sdl2.ext.draw.fill(self.mapSurface, sdl2.ext.Color(color,color,color,255), (posX, posY, MAP_SCALE - 1, MAP_SCALE - 1))
def drawRays(self):
sdl2.ext.draw.fill(self.raycastSurface, CEILING_COLOR, (0, 0, RAYCAST_WIN_WIDTH, RAYCAST_WIN_HEIGHT/2)) # Clears upper raycast screen (draws ceiling)
sdl2.ext.draw.fill(self.raycastSurface, FLOOR_COLOR, (0, RAYCAST_WIN_HEIGHT/2, RAYCAST_WIN_WIDTH, RAYCAST_WIN_HEIGHT/2)) # Clears upper raycast screen (draws floor)
# Casts rays for raycasting
playerAngle = self.player_position["r"]
# Cast one ray for every window pixel, from -0,5 rads to +0,5 rads (about 60° viewing angle)
for i in range(RAYCAST_RENDER_WIDTH):
rayAngle = playerAngle + (i/RAYCAST_RENDER_WIDTH) - 0.5
if rayAngle < 0:
rayAngle = math.pi * 2 + rayAngle
if rayAngle > math.pi * 2:
rayAngle = rayAngle - math.pi * 2
# Which map wall tiles have been hit by rayX and rayY
mapBlockHitX = 0
mapBlockHitY = 0
# Check horizontal lines
dof = 0 # Depth of field
if rayAngle == 0 or rayAngle == math.pi:
# Looking left or right (ray will never intersect parallel lines)
rayY = self.player_position["y"]
rayX = self.player_position["x"] + DOF * MAP_SCALE
dof = DOF # Set depth of field to maximum to avoid unneeded checks
elif rayAngle > math.pi:
# Looking up
aTan = -1/math.tan(rayAngle)
rayY = (int(self.player_position["y"] / MAP_SCALE) * MAP_SCALE) - 0.00001
rayX = (self.player_position["y"] - rayY) * aTan + self.player_position["x"]
yOffset = -MAP_SCALE
xOffset = -yOffset * aTan
else:
# Looking down
aTan = -1/math.tan(rayAngle)
rayY = (int(self.player_position["y"] / MAP_SCALE) * MAP_SCALE) + MAP_SCALE
rayX = (self.player_position["y"] - rayY) * aTan + self.player_position["x"]
yOffset = MAP_SCALE
xOffset = -yOffset * aTan
# Check if we reached a wall
while dof < DOF:
mapX = int(rayX / MAP_SCALE)
mapY = int(rayY / MAP_SCALE)
mapArrayPosition = mapY * MAP_SIZE + mapX
if mapArrayPosition >= 0 and mapArrayPosition < MAP_SIZE*MAP_SIZE and MAP[mapArrayPosition] != 0:
dof = DOF # Hit the wall: we are done, no need to do other checks
mapBlockHitY = MAP[mapArrayPosition] # Save which map wall tile we reached
else:
# Didn't hit the wall: check successive horizontal line
rayX = rayX + xOffset
rayY = rayY + yOffset
dof = dof + 1
# Save horyzontal probe rays for later comparison with vertical
horizRayX = rayX
horizRayY = rayY
# Check vertical lines
dof = 0 # Depth of field
nTan = -math.tan(rayAngle)
xOffset = 0
yOffset = 0
if rayAngle == math.pi * 0.5 or rayAngle == math.pi * 1.5:
#if rayAngle == 0 or rayAngle == math.pi:
# Looking up or down (ray will never intersect vertical lines)
rayX = self.player_position["x"]
rayY = self.player_position["y"] + DOF * MAP_SCALE
dof = DOF # Set depth of field to maximum to avoid unneeded checks
elif rayAngle > math.pi * 0.5 and rayAngle < math.pi * 1.5:
# Looking left
rayX = (int(self.player_position["x"] / MAP_SCALE) * MAP_SCALE) - 0.00001
rayY = (self.player_position["x"] - rayX) * nTan + self.player_position["y"]
xOffset = -MAP_SCALE
yOffset = -xOffset * nTan
else:
# Looking right
rayX = (int(self.player_position["x"] / MAP_SCALE) * MAP_SCALE) + MAP_SCALE
rayY = (self.player_position["x"] - rayX) * nTan + self.player_position["y"]
xOffset = MAP_SCALE
yOffset = -xOffset * nTan
# Check if we reached a wall
while dof < DOF:
mapX = int(rayX / MAP_SCALE)
mapY = int(rayY / MAP_SCALE)
mapArrayPosition = mapY * MAP_SIZE + mapX
if mapArrayPosition >= 0 and mapArrayPosition < MAP_SIZE*MAP_SIZE-1 and MAP[mapArrayPosition] != 0:
dof = DOF # Hit the wall: we are done, no need to do other checks
mapBlockHitX = MAP[mapArrayPosition] # Save which map wall tile we reached
else:
# Didn't hit the wall: check successive horizontal line
rayX = rayX + xOffset
rayY = rayY + yOffset
dof = dof + 1
horizDist = self.dist(self.player_position["x"], self.player_position["y"], horizRayX, horizRayY)
vertDist = self.dist(self.player_position["x"], self.player_position["y"], rayX, rayY)
shortestDist = vertDist
if vertDist > horizDist:
rayX = horizRayX
rayY = horizRayY
shortestDist = horizDist
if not MAP_HIDDEN:
# Draw rays in 2D view
sdl2.ext.draw.line(self.mapSurface, sdl2.ext.Color(0,0,255,255), (self.player_position["x"], self.player_position["y"], rayX, rayY))
# ------ Draw 3D view ------
# Calculate line height based on distance
lineHeight = MAP_SCALE * RAYCAST_RENDER_HEIGHT / shortestDist
# Center line vertically in window
lineOffset = RAYCAST_RENDER_HEIGHT / 2 - lineHeight / 2
# Draw pixels vertically from top to bottom to obtain a line
textureSegmentEnd = 0
for textureColumnPixel in range(0, TEXTURE_SIZE):
# Calc texture segment length on screen
textureSegmentLength = lineHeight / TEXTURE_SIZE
if textureSegmentEnd == 0:
# First iteration: calculate segment start
textureSegmentStart = lineOffset + textureColumnPixel * textureSegmentLength
else:
# Next iterations: use the previous segment end (avoids rounding errors)
textureSegmentStart = textureSegmentEnd
textureSegmentEnd = textureSegmentStart + textureSegmentLength
# Obtain texture value in the pixel representing the current segment and calculate shading
if vertDist > horizDist:
texIndex = mapBlockHitY - 1 # The texture covering the selected map tile (0 is no texture, 1 is texture at self.textures[0] etc)
texColumn = int(rayX / (MAP_SCALE / TEXTURE_SIZE) % TEXTURE_SIZE)
shading = True
else:
texIndex = mapBlockHitX - 1 # The texture covering the selected map tile
texColumn = int(rayY / (MAP_SCALE / TEXTURE_SIZE) % TEXTURE_SIZE)
shading = False
# Obtain texture pixel color
color = self.textures[texIndex][texColumn + textureColumnPixel * TEXTURE_SIZE]
# Calculate color resulting from texture pixel value + shading
if shading:
color = self.shade(color)
# Clipping
lineEnd = textureSegmentEnd
if lineEnd > RAYCAST_RENDER_HEIGHT:
lineEnd = RAYCAST_RENDER_HEIGHT
lineStart = textureSegmentStart
if lineStart < 0:
lineStart = 0
if lineEnd < lineStart:
continue
# Upscaling
lineStart = lineStart * RAYCAST_RESOLUTION_SCALING
lineEnd = lineEnd * RAYCAST_RESOLUTION_SCALING
# Draw segment
for repeat in range(1, RAYCAST_RESOLUTION_SCALING + 1):
x = i * RAYCAST_RESOLUTION_SCALING + repeat
self.drawVline(self.raycastSurface, color, x, int(lineStart), int(lineEnd))
def drawVline(self, surface, color, x, startY, endY):
if x < 0 or x > RAYCAST_WIN_WIDTH or startY < 0 or endY > RAYCAST_WIN_HEIGHT or endY < startY:
print("Trying to write outside bounds: vertical line with x {} from y {} to y {}".format(x, startY, endY))
return
startIdx = startY * RAYCAST_WIN_WIDTH + x
for idx in range(startIdx, endY * RAYCAST_WIN_WIDTH + x, RAYCAST_WIN_WIDTH):
self.raycast_u32_pixels[idx] = color
def shade(self, color):
# Obtain channels
b = color & 0b000000000000000011111111
g = color >> 8 & 0b000000000000000011111111
r = color >> 16 & 0b000000000000000011111111
# Dim channels (and limit to 255, because python doesn't have a fixed byte length)
b = (b >> 1)
g = (g >> 1)
r = (r >> 1)
# Compose color
return b + (g << 8) + (r << 16)
def dist(self, ax, ay, bx, by):
return math.sqrt((bx-ax)*(bx-ax) + (by-ay)*(by-ay))
def loadTexture(self, pngFilePath):
# Loads a texture from png file and converts to sdl2-friendly format
reader = png.Reader(filename=pngFilePath)
w, h, pixels, metadata = reader.read_flat()
if metadata['alpha']:
raise ValueError("Textures with alpha channel are not supported")
if w != TEXTURE_SIZE or h != TEXTURE_SIZE:
raise ValueError("Texture {} is not {}x{}, but {}x{}".format(pngFilePath, TEXTURE_SIZE, TEXTURE_SIZE, w, h))
# Convert to sdl2-friendly format
converted = []
for i in range(0, len(pixels), 3):
# PNG is RGB, SDL surface is BGR
converted.append(pixels[i+2] + (pixels[i+1] << 8) + (pixels[i] << 16)) # BGR
return converted
if __name__ == '__main__':
try:
main = Main()
main.run()
except KeyboardInterrupt:
exit(0)