Files
Py-Caster/py_caster.py
2017-11-08 17:36:20 -04:00

520 lines
20 KiB
Python
Executable File

#! /usr/bin/env python
import math
import pygame
##############################################################
# Game parameters
##############################################################
TITLE = "Py Caster"
FPS = 30
SCREEN_SIZE = (800, 600)
FILL_COLOR = (0, 0, 0)
FAR = 5.0
TOLERANCE = 0.000001
FLOOR_TEXTURE = "Textures/goldlites.jpg"
CEIL_TEXTURE = "Textures/brownstone.jpg"
SKY_TEXTURE = "Textures/starynight.png"
##############################################################
# Projection parameters
##############################################################
FB_SIZE = (320, 200)
DEG2RAD = 3.1415926535897932384626433 / 180.0
RAD2DEG = 180.0 / 3.1415926535897932384626433
FOV = 0.0
ANGLE_INCREMENT = 0.0
HEIGHT_CLAMP_MULTIPLER = 10 # MUST BE AN INTEGER
##############################################################
# Player parameters
##############################################################
PLAYER_TURN_SPEED = 2.0 * DEG2RAD
PLAYER_MOVE_SPEED = 0.1
##############################################################
# Vector Classes
##############################################################
class vec(object):
def __ini__(self):
pass
def length(self):
return math.sqrt(self.dot(self))
def lengthSQ(self):
return self.dot(self)
def distance(self, p):
return p.sub(self).length()
def distanceSQ(self, p):
return p.sub(self).lengthSQ()
class vec3(vec):
def __init__(self, x = 0, y = 0, z = 0):
self.x = x
self.y = y
self.z = z
def __str__(self):
return "(" + str(self.x) + ", " + str(self.y) + ", " + str(self.z) + ")"
def add(self, v):
return vec3(self.x + v.x, self.y + v.y, self.z + v.z)
def sub(self, v):
return vec3(self.x - v.x, self.y - v.y, self.z - v.z)
def scale(self, k):
return vec3(self.x * k, self.y * k, self.z * k)
def dot(self, v):
return (self.x * v.x) + (self.y * v.y) + (self.z * v.z)
def normalize(self):
norm = self.length()
if norm > 0:
self.x /= norm
self.y /= norm
self.z /= norm
return self
def mix(self, v, t):
return vec3((self.x * t) + (v.x * (1.0 - t)), (self.y * t) + (v.y * (1.0 - t)), (self.z * t) + (v.z * (1.0 - t)))
class vec2(vec):
def __init__(self, x = 0, y = 0):
self.x = x
self.y = y
def __str__(self):
return "(" + str(self.x) + ", " + str(self.y) + ")"
def add(self, v):
return vec2(self.x + v.x, self.y + v.y)
def sub(self, v):
return vec2(self.x - v.x, self.y - v.y)
def scale(self, k):
return vec2(self.x * k, self.y * k)
def dot(self, v):
return (self.x * v.x) + (self.y * v.y)
def normalize(self):
norm = self.length()
if norm > 0:
self.x /= norm
self.y /= norm
return self
def cross(self, v):
return vec3(0.0, 0.0, (self.x * v.y) - (self.y * v.x))
def mix(self, v, t):
return vec2((self.x * t) + (v.x * (1.0 - t)), (self.y * t) + (v.y * (1.0 - t)))
##############################################################
# Ray Class
##############################################################
class Ray(object):
def __init__(self, origin = vec2(0.0, 0.0), direction = vec2(0.0, 1.0)):
self.o = origin
self.d = direction.normalize()
def __str__(self):
return "Origin: " + str(self.o) + " :: Direction: " + str(self.d)
##############################################################
# Intersection Class
##############################################################
class Intersection(object):
def __init__(self, r, t, tex_coord = None):
self.p = r.o.add(r.d.scale(t))
self.d = r.o.distance(self.p)
self.tc = tex_coord
##############################################################
# Line Segment Class
##############################################################
class LineSegment(object):
def __init__(self, a, b, tca, tcb, texture):
self.a = a
self.b = b
self.v = b.sub(a).normalize()
self.n = vec2(-self.v.y, self.v.x)
self.tca = tca
self.tcb = tcb
self.texture = pygame.image.load(texture).convert()
def intersect(self, r):
def classifyPoint2D(point):
v1 = point.sub(self.a).normalize()
return v1.dot(self.n)
def sign(n):
if n == 0:
return 0
elif n > 0:
return 1
else:
return -1
def lerp(a, b, t):
return (a * t) + (b * (1.0 - t))
side = classifyPoint2D(r.o)
v2 = self.b.sub(self.a)
v3 = vec2(-r.d.y, r.d.x) if sign(side) > 0 else vec2(r.d.y, -r.d.x)
det = v2.dot(v3)
if abs(det) < TOLERANCE:
return None
else:
v1 = r.o.sub(self.a)
t1 = v2.cross(v1).length() / det
t2 = v1.dot(v3) / det
if t2 >= 0.0 and t2 <= 1.0 and t1 > 0.0:
return Intersection(r, t1, lerp(self.tca, self.tcb, t2))
else:
return None
def get_tex_column(self, s):
w = self.texture.get_width()
h = self.texture.get_height()
_s = s * w if s >= 0.0 else (1.0 - (math.ceil(s) - s)) * w
_s = int(_s % w)
# Creating a subsurface is pretty fast in pygame, no copying of pixels is needed
return self.texture.subsurface(pygame.Rect(_s, 0, 1, h))
##############################################################
# Plane3D class
##############################################################
class Plane3d(object):
def __init__(self, texture):
self.texture = pygame.image.load(texture).convert()
def sample_texture(self, st):
w = self.texture.get_width()
h = self.texture.get_height()
s = st.x * w if st.x >= 0.0 else (1.0 - (math.ceil(st.x) - st.x)) * w
s = int(s % w)
t = st.y * h if st.y >= 0.0 else (1.0 - (math.ceil(st.y) - st.y)) * h
t = int(t % h)
return pygame.Rect(s, t, 1, 1)
##############################################################
# Sprite class
##############################################################
class Sprite(object):
def __init__(self, position, texture):
self.p = position
self.d = 0.0
self.texture = pygame.image.load(texture).convert_alpha()
def sample_texture(self, s):
_s = s % self.texture.get_width()
# Creating a subsurface is pretty fast in pygame, no copying of pixels is needed
return self.texture.subsurface(pygame.Rect(_s, 0, 1, self.texture.get_height()))
##############################################################
# Sky class
##############################################################
class Sky(object):
def __init__(self, texture):
self.texture = pygame.image.load(texture).convert_alpha()
def sample_texture(self, angle):
s = int((angle / 90.0) * self.texture.get_width()) % self.texture.get_width()
return self.texture.subsurface(pygame.Rect(s, 0, 1, self.texture.get_height()))
##############################################################
# Main Function
##############################################################
def main():
global FOV, ANGLE_INCREMENT
# Local variables.
done = False
toggle_sky = True
sky_enabled = False
player_pos = vec2(0.0, 0.0)
player_dir = vec2(-1.0, 0.0)
plane = vec2(0.0, 0.66)
arrow_keys = {
pygame.K_UP: False,
pygame.K_DOWN: False,
pygame.K_LEFT: False,
pygame.K_RIGHT: False,
pygame.K_w: False,
pygame.K_a: False,
pygame.K_s: False,
pygame.K_d: False
}
# Update global variables
FOV = 2.0 * math.atan((plane.length() / player_dir.length())) * RAD2DEG
ANGLE_INCREMENT = FOV / float(FB_SIZE[0])
# Initialize Pygame.
pygame.init()
clock = pygame.time.Clock()
screen = pygame.display.set_mode(SCREEN_SIZE, pygame.HWSURFACE | pygame.DOUBLEBUF)
frame_buffer = pygame.Surface(FB_SIZE, pygame.HWSURFACE)
pygame.mouse.set_visible(False)
pygame.key.set_repeat(17, 17)
# Define walls, floor and ceiling.
walls = [
LineSegment(vec2(3.0, 3.0), vec2(3.0, -3.0), 0.0, 6.0, "Textures/metal.jpg"),
LineSegment(vec2(3.0, -3.0), vec2(-3.0, -3.0), 0.0, 6.0, "Textures/metal.jpg"),
LineSegment(vec2(-3.0, -3.0), vec2(-3.0, 3.0), 0.0, 6.0, "Textures/metal.jpg"),
LineSegment(vec2(2.0, 2.0), vec2(3.0, 3.0), 0.0, 1.0, "Textures/diagmetal.jpg"),
LineSegment(vec2(-2.0, 2.0), vec2(-3.0, 3.0), 0.0, 1.0, "Textures/diagmetal.jpg"),
LineSegment(vec2(-2.0, 2.0), vec2(2.0, 2.0), 0.0, 4.0, "Textures/diagmetal.jpg"),
LineSegment(vec2(-0.5, -1.0), vec2(-1.5, -3.0), vec2(-1.5, -3.0).sub(vec2(-0.5, -1.0)).length(), 0.0, "Textures/orangetiles.jpg"),
LineSegment(vec2(-0.5, -1.0), vec2(0.5, -1.0), 0.0, 1.0, "Textures/orangetiles.jpg"),
LineSegment(vec2(0.5, -1.0), vec2(1.5, -3.0), vec2(1.5, -3.0).sub(vec2(0.5, -1.0)).length(), 0.0, "Textures/orangetiles.jpg")
]
floor = Plane3d(FLOOR_TEXTURE)
ceiln = Plane3d(CEIL_TEXTURE)
sky = Sky(SKY_TEXTURE)
sprites = [
Sprite(vec2(-1.5, -2.0), "Textures/bag.png"),
Sprite(vec2(1.5, -2.0), "Textures/bag.png")
]
# Main game loop.
try:
while(not done):
fps = clock.get_fps() + 0.001
pygame.display.set_caption(TITLE + ": " + str(int(fps)))
# Input capture.
for event in pygame.event.get():
# Quit on escape key or window close
if (event.type == pygame.KEYDOWN and event.key == pygame.K_ESCAPE) or event.type == pygame.QUIT:
done = True
if event.type == pygame.KEYDOWN and event.key == pygame.K_SPACE and toggle_sky:
toggle_sky = False
sky_enabled = not sky_enabled
elif event.type == pygame.KEYUP and event.key == pygame.K_SPACE and not toggle_sky:
toggle_sky = True
# Record wich keys were pressed and released this frame
try:
if event.type == pygame.KEYDOWN:
arrow_keys[event.key] = True
elif event.type == pygame.KEYUP:
arrow_keys[event.key] = False
except KeyError:
pass
# Camera movement
if arrow_keys[pygame.K_UP] or arrow_keys[pygame.K_w]:
player_pos = player_pos.add(player_dir.scale(PLAYER_MOVE_SPEED))
if arrow_keys[pygame.K_DOWN] or arrow_keys[pygame.K_s]:
player_pos = player_pos.sub(player_dir.scale(PLAYER_MOVE_SPEED))
if arrow_keys[pygame.K_a]:
perp = vec2(-player_dir.y, player_dir.x).normalize()
player_pos = player_pos.add(perp.scale(PLAYER_MOVE_SPEED))
if arrow_keys[pygame.K_d]:
perp = vec2(player_dir.y, -player_dir.x).normalize()
player_pos = player_pos.add(perp.scale(PLAYER_MOVE_SPEED))
if arrow_keys[pygame.K_LEFT]:
# Apply a rotation matrix to the view and projection vectors
oldDirX = player_dir.x;
player_dir.x = player_dir.x * math.cos(PLAYER_TURN_SPEED) - player_dir.y * math.sin(PLAYER_TURN_SPEED);
player_dir.y = oldDirX * math.sin(PLAYER_TURN_SPEED) + player_dir.y * math.cos(PLAYER_TURN_SPEED);
oldPlaneX = plane.x;
plane.x = plane.x * math.cos(PLAYER_TURN_SPEED) - plane.y * math.sin(PLAYER_TURN_SPEED);
plane.y = oldPlaneX * math.sin(PLAYER_TURN_SPEED) + plane.y * math.cos(PLAYER_TURN_SPEED);
if arrow_keys[pygame.K_RIGHT]:
# Apply a rotation matrix to the view and projection vectors
oldDirX = player_dir.x;
player_dir.x = player_dir.x * math.cos(-PLAYER_TURN_SPEED) - player_dir.y * math.sin(-PLAYER_TURN_SPEED);
player_dir.y = oldDirX * math.sin(-PLAYER_TURN_SPEED) + player_dir.y * math.cos(-PLAYER_TURN_SPEED);
oldPlaneX = plane.x;
plane.x = plane.x * math.cos(-PLAYER_TURN_SPEED) - plane.y * math.sin(-PLAYER_TURN_SPEED);
plane.y = oldPlaneX * math.sin(-PLAYER_TURN_SPEED) + plane.y * math.cos(-PLAYER_TURN_SPEED);
# Clear the screen
#frame_buffer.fill(FILL_COLOR)
# Render walls.
angle = -FOV / 2.0
depth_buffer = [0 for x in xrange(FB_SIZE[0])]
p_angle = 360.0 - (math.atan2(player_dir.y, player_dir.x) * RAD2DEG)
for i in xrange(FB_SIZE[0]):
if sky_enabled and h < FB_SIZE[1]:
sky_angle = (p_angle + angle) % 360.0
sky_angle = 360.0 - sky_angle if sky_angle < 0.0 else sky_angle
stex = sky.sample_texture(sky_angle)
frame_buffer.blit(stex, (i, 0))
# Generate camera ray
camera_x = 2.0 * (float(i) / float(FB_SIZE[0])) - 1;
r = Ray(vec2(player_pos.x, player_pos.y), player_dir.add(plane.scale(camera_x)))
d = float('Inf')
c = None
p = None
h = 0
# Check each wall for an intersection
for l in walls:
intersection = l.intersect(r)
if intersection is not None:
# If an intersection was found then keep it if it's closer than the previous one
if intersection.d < d:
d = intersection.d
c = l.get_tex_column(intersection.tc)
p = intersection.p
depth_buffer[i] = d
if c is not None:
# If an intersection was found then compute the projected height of the wall in pixels
h = int(float(FB_SIZE[1]) / (d * math.cos(angle * DEG2RAD)))
# The height tends to infinity as we get close to the walls so it must be clamped
h = HEIGHT_CLAMP_MULTIPLER * FB_SIZE[1] if h > HEIGHT_CLAMP_MULTIPLER * FB_SIZE[1] else h
# Then scale the corresponding texture slice and blit it
scaled = pygame.transform.scale(c, (c.get_width(), h))
frame_buffer.blit(scaled, (i, -(h / 2) + (FB_SIZE[1] / 2)))
# Darken wall according to distance
_d = (d if d < FAR else FAR) / FAR
depth = 255 - int(_d * 255)
frame_buffer.fill((depth, depth, depth),
pygame.Rect(i,
-(h / 2) + (FB_SIZE[1] / 2) if -(h / 2) + (FB_SIZE[1] / 2) >= 0 else 0,
1,
scaled.get_height() if scaled.get_height() < FB_SIZE[1] else FB_SIZE[1] - 1),
pygame.BLEND_MULT)
# Floor casting and ceiling casting
if p is not None and h > 0 and h < FB_SIZE[1]:
for j in xrange((h / 2) + (FB_SIZE[1] / 2), FB_SIZE[1] + 1):
det = (2.0 * j - FB_SIZE[1])
if det > 0.0:
cd = FB_SIZE[1] / det
weight = cd / (d * math.cos(angle * DEG2RAD))
st = vec2((weight * p.x) + ((1.0 - weight) * player_pos.x), (weight * p.y) + ((1.0 - weight) * player_pos.y))
# Sample floor
ftex = floor.sample_texture(st)
# Draw floor
frame_buffer.blit(floor.texture, (i, j), ftex)
# Darken floor according to distance
_d = (cd if cd < FAR else FAR) / FAR
depth = 255 - int(_d * 255)
frame_buffer.fill((depth, depth, depth), pygame.Rect(i, j, 1, 1), pygame.BLEND_MULT)
# Draw ceiling
if not sky_enabled:
ctex = ceiln.sample_texture(st)
frame_buffer.blit(ceiln.texture, (i, FB_SIZE[1] - j), ctex)
frame_buffer.fill((depth, depth, depth), pygame.Rect(i, FB_SIZE[1] - j, 1, 1), pygame.BLEND_MULT)
angle += ANGLE_INCREMENT
# Sort the sprites by distance
for s in sprites:
s.d = player_pos.distanceSQ(s.p)
sprites.sort(key = lambda s: s.d, reverse = True)
# Render the sprites
for s in sprites:
# Take sprite to eye space
sp_eye = s.p.sub(player_pos)
# Apply inverse camera matrix to sp_eye
inv_det = 1.0 / ((plane.x * player_dir.y) - (player_dir.x * plane.y))
tx = inv_det * ((player_dir.y * sp_eye.x) - (player_dir.x * sp_eye.y))
ty = inv_det * ((-plane.y * sp_eye.x) + (plane.x * sp_eye.y))
# If the sprite is behind the eye there is no need to continue with this sprite
if ty <= 0.0:
continue
# Compute sprite x position in image space, width and height
sp_screen_x = int((FB_SIZE[0] / 2) * (1.0 + (tx / ty)))
sh = int(abs(FB_SIZE[1] / ty))
sw = sh # The sprites are always square
# Compute draw rows
draw_start_y = int((-sh / 2) + (FB_SIZE[1] / 2))
draw_start_y = 0 if draw_start_y < 0 else draw_start_y
draw_end_y = int((sh / 2) + (FB_SIZE[1] / 2))
draw_end_y = FB_SIZE[1] - 1 if draw_end_y >= FB_SIZE[1] else draw_end_y
# Compute draw cols
draw_start_x = int((-sw / 2) + sp_screen_x)
draw_start_x = 0 if draw_start_x < 0 else draw_start_x
draw_end_x = int((sw / 2) + sp_screen_x)
draw_end_x = FB_SIZE[0] if draw_end_x >= FB_SIZE[0] else draw_end_x
# Draw columns
tw = s.texture.get_width()
for i in xrange(draw_start_x, draw_end_x):
# Compute tex coord of sprite slice
tc = int((i - (-sw / 2 + sp_screen_x)) * tw / sw)
# Draw only if the sprite slice is actually inside the screen and there are no walls in front of it
if i >= 0 and i < FB_SIZE[0] and ty < depth_buffer[i]:
# Get texture slice and scale it to it's on-screen height
c = s.sample_texture(tc)
scaled = pygame.transform.scale(c, (c.get_width(), sh))
# Darken the texture by distance
_d = (ty if ty < FAR else FAR) / FAR
depth = 255 - int(_d * 255)
scaled.fill((depth, depth, depth, 1.0),
pygame.Rect(0,
0,
1,
sh),
pygame.BLEND_MULT
)
# Draw the sprite
frame_buffer.blit(scaled, (i, draw_start_y))
# Render framebuffer to the screen
pygame.transform.scale(frame_buffer, SCREEN_SIZE, screen)
# Update screen
pygame.display.update()
clock.tick(FPS)
except KeyboardInterrupt:
pass
pygame.quit()
if __name__ == "__main__":
main()