scene.s

# A scene must export the following symbols

# <filename>
# - asciiz string, including the ".bmp" extension
# <image.width>
# - unsigned word
# <image.height>
# - unsigned word

# <camera>
# four 3-vectors of doubles
# - location
# - direction
# - right (Length of vector = width of frame)
# - up (Length of vector = height of frame)
# - word 0,1,2,3,4,5 -> Camera X,Y,Z
# - word 6,7,8,9,10,11 -> Corner X,Y,Z
# - word 12,13,14,15,16,17 -> Right X,Y,Z
# - word 18,19,20,21,22,23 -> Up X,Y,Z

# <objects> (Allocate 22 Words for each object)
# linked list. pointer in word 0; data follows
# - word 0 -> next <objects> node or 0
# - word 1 -> type
# - word 2,3 -> ColorR
# - word 4,5 -> ColorG
# - word 6,7 -> ColorB
# - word 8 -> Reflectivity
# - word 9 -> Shininess
# - subsequent words type-specific

# <lights>
# - null-terminated list of pairs
# - each pair has 3-vectors for position and color
# - word 0 -> next light (or 0)
# - word 2,3 -> X Position
# - word 4,5 -> Y Position
# - word 6,7 -> Z Position
# - word 8,9 -> R
# - word 10,11 -> G
# - word 12,13 -> B

# Entities that are not exported

# Rays
# - words 0,1,2,3,4,5 -> Point from which the ray starts
# - words 6,7,8,9,10,11 -> Unit Vector in Direction of Ray

# the type of an object is
# - 0 = sphere
# - fields position, radius (8 Words total)
# - 1 = plane
# - fields point on plane, normal (12 Words total)

# ********************************
# This Scene takes 1-2 mins to run
# ********************************
	.data
	.globl filename
# The output file name:
filename:	.asciiz "outputimage.bmp"
	.globl camera
# The Camera/Frame
camera:	.double 0.0,-10.0,4.0	# Camera
	.double -6.4,0.0,0.0	# Corner
	.double 12.8,0.0,0.0	# Right
	.double 0.0,0.0,8.0	# Up

	.globl width
	.globl height
# Width and Height of Picture, in Pixels
width:	.word 128
height:	.word 80

	.globl recurseLevels
# The number of levels of recursion
recurseLevels:	.word 10

	.globl objects
	.globl lights
	.globl ambient
	.globl diffuse
	.globl background
objects:	.word 0		# Pointer to first element of objects list
lights:		.word 0		# Pointer to first element of lights list
# These Should Sum to 1
ambient:	.double 0.2, 0.2, 0.2	# Ambient Coefficient
diffuse:	.double 0.8, 0.8, 0.8	# Diffuse Coefficient
background:	.double 0.0, 0.0, 0.0		# Background Color

# Object Variables
plane1:		.word 0,1	# Pointer, Type
		.double 0.3,0.3,0.3	# Color
		.double 0.8		# Reflectivity
		.double 0.0,0.0,0.0	# Point
		.double 0.0,0.0,1.0	# Normal
plane2:		.word 0,1	# Pointer, Type
		.double 0.4,0.4,0.4	# Color
		.double 0.6		# Reflectivity
		.double -5.0,0.0,0.0	# Point
		.double -0.9701,0.2425,0.0	# Normal
plane3:		.word 0,1	# Pointer, Type
		.double 0.4,0.4,0.4	# Color
		.double 0.6		# Reflectivity
		.double 5.0,0.0,0.0	# Point
		.double -0.9701,-0.2425,0.0	# Normal
sphere1:	.word 0,0	# Pointer, Type
		.double 0.551,0.0,0.578	# Color
		.double 0.7		# Reflectivity
		.double 0.0,6.0,2.5	# Center
		.double 2.0,0.0,0.0	# Radius
sphere2:	.word 0,0	# Pointer, Type
		.double 0.0,0.773,0.0	# Color
		.double 0.7		# Reflectivity
		.double -8.0,12.0,8.0	# Center
		.double 2.0,0.0,0.0	# Radius
sphere3:	.word 0,0	# Pointer, Type
		.double 0.777,0.0,0.0	# Color
		.double 0.7		# Reflectivity
		.double 8.0,12.0,8.0	# Center
		.double 2.0,0.0,0.0	# Radius
sphere4:	.word 0,0	# Pointer, Type
		.double 0.043,0.430,1.0	# Color
		.double 0.7		# Reflectivity
		.double -6.0,8.0,3.0	# Center
		.double 2.0,0.0,0.0	# Radius
sphere5:	.word 0,0	# Pointer, Type
		.double 0.0,0.805,1.0	# Color
		.double 0.7		# Reflectivity
		.double 6.0,8.0,3.0	# Center
		.double 2.0,0.0,0.0	# Radius
sphere6:	.word 0,0	# Pointer, Type
		.double 0.0,0.0,0.777	# Color
		.double 0.7		# Reflectivity
		.double 0.0,8.0,7.0	# Center
		.double 2.0,0.0,0.0	# Radius
sphere7:	.word 0,0	# Pointer, Type
		.double 0.7,0.7,0.7	# Color
		.double 0.7		# Reflectivity
		.double -20.0,23.5,-10.0	# Center
		.double 3.5,0.0,0.0	# Radius
light1:		.word 0,0
		.double -6.4,0.0,10.0	# Position
		.double 1.0,1.0,1.0	# Color
light2:		.word 0,0
		.double 6.4,0.0,10.0	# Position
		.double 1.0,1.0,1.0	# Color
light3:		.word 0,0
		.double -6.4,0.0,8.0	# Position
		.double 1.0,1.0,1.0	# Color
light4:		.word 0,0
		.double 6.4,0.0,8.0	# Position
		.double 1.0,1.0,1.0	# Color
	.text
	.globl scene.init
scene.init:
	# Initialize objects linked list
	la $t0, objects
	la $t1, plane1
	sw $t1, 0($t0)	# Make "objects" point to "plane1"
	la $t0, sphere1
	sw $t0, 0($t1)	# Make "plane1" point to "sphere12"
	la $t1, sphere2
	sw $t1, 0($t0)	# Make "sphere1" point to "sphere2"
	la $t0, sphere3
	sw $t0, 0($t1)	# Make "sphere2" point to "sphere3"
	la $t1, sphere4
	sw $t1, 0($t0)	# Make "sphere3" point to "sphere4"
	la $t0, sphere5
	sw $t0, 0($t1)	# Make "sphere4" point to "sphere5"
	la $t1, sphere6
	sw $t1, 0($t0)	# Make "sphere5" point to "sphere6"
	#la $t0, sphere7
	#sw $t0, 0($t1)

	# Initialize lights linked list
	la $t0, lights
	la $t1, light1
	sw $t1, 0($t0)	# Make "lights" point to "light1"
	la $t0, light2
	sw $t0, 0($t1)	# Make "light1" point to "light2"
	#la $t1, light3
	#sw $t1, 0($t0)
	#la $t0, light4
	#sw $t0, 0($t1)
	jr $ra