Strings in POVLANG.TXT
Persistence of Vision Raytracer
Version 1.0
Quick Reference
-------------------------------
By Chris Young
This is a formal grammar definition of the POV-Ray scene description
language. It is based on PARSE.C and TOKENIZE.C from version 1.0 of POV-Ray.
See POVRAY.DOC for in-depth description of the program and language
The POV-Ray language is used to describe something called a FRAME. Everything
needed to render that image is stored in a text file describing that FRAME.
Also note,
#include "filename.inc"
can appear anywhere in the text to include text from another file.
The parser will behave as if all the text from filename.inc were inserted
at that point in the file.
Note that the use of "#" is currently optional, but recommended for
readability when using include and declare for readability. This will be
mandatory in future versions.
Any text following "//" to the end of the line is ignored as comments.
Furthermore text between "/*" and "*/" is considered a comment.
/* */ comments can be nested.
In the notation used below in general a single character in quotes is that
literal character. All lower case words are also literal and they are
reserved keywords. Upper case words denote language constructs.
An ellipsis denotes one or more. Square brackets denote optional.
A bar | denotes a choice of item or items.
A scroll bracket is a literal "{" or "}" but the quotes have been
omitted for clarity.
For example:
ITEM one occurrence of ITEM
ITEM... one or more occurrences of ITEM
[ITEM] zero or one occurrence of ITEM
[ITEM...] zero or more occurrences of ITEM
ITEM_1 | ITEM_2 one occurrence of either ITEM_1 or ITEM_2
NOTE: STRING is defined as a string of characters in quotes
IDENTIFIER is an alphabetic character followed by one or more
alphanumerics or underscores
ITEM_IDENTIFIER is an IDENTIFIER of type ITEM
Leave questions/comments to Chris Young CIS:[76702,1655]
--------------------------------------------------------------
DIGIT = "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"
POINT = "."
EXP = "e" | "E"
SIGN = "+" | "-"
FLOAT_CONST = [DIGIT...] [POINT] DIGIT... [EXP [SIGN] DIGIT...]
FLOAT = [SIGN] FLOAT_CONST | [SIGN] FLOAT_IDENTIFIER
COLOR_ITEM = red FLOAT | green FLOAT | blue FLOAT |
alpha FLOAT | COLOR_IDENTIFIER
COLOR_SPEC = color [COLOR_ITEM...]
Note:"color" and "colour" can be used interchangeably everywhere.
COLOR_MAP_ENTRY = "[" FLOAT FLOAT COLOR_SPEC COLOR_SPEC "]"
COLOR_MAP = color_map { [COLOR_MAP_ENTRY...] }
VECTOR = "<" FLOAT FLOAT FLOAT ">"
MAP_PREFIX = FLOAT | VECTOR
MAP_FILE = iff STRING |
tga STRING |
gif STRING |
dump STRING
IMAGE_ATTRIB= once |
interpolate FLOAT |
map_type FLOAT |
use_color |
use_index |
alpha all FLOAT |
alpha FLOAT FLOAT
BUMP_ATTRIB = once |
interpolate FLOAT |
map_type FLOAT |
bump_size FLOAT |
use_color |
use_index
MATER_ATTRIB= once |
interpolate FLOAT |
map_type FLOAT |
TEXTURE
TEXTURE_ITEM= TEXTURE_IDENTIFIER |
FLOAT |
once |
turbulence FLOAT |
octaves FLOAT |
brick color COLOR_SPEC color COLOR_SPEC |
mortar FLOAT |
checker [COLOR_SPEC [COLOR_SPEC]] |
tiles { [TEXTURE] tile2 [TEXTURE] } |
bozo | marble | wood | spotted | agate |
granite | metallic | onion | leopard |
painted1 | painted2 | painted3 |
gradient VECTOR |
ambient FLOAT |
brilliance FLOAT |
roughness FLOAT |
phong_size FLOAT |
diffuse FLOAT |
specular FLOAT |
phong FLOAT |
ior FLOAT |
refraction FLOAT |
reflection FLOAT |
waves FLOAT [phase FLOAT] |
frequency FLOAT |
phase FLOAT |
ripples FLOAT |
wrinkles FLOAT |
bumps FLOAT |
dents FLOAT |
translate VECTOR |
rotate VECTOR |
scale VECTOR |
COLOR_SPEC |
COLOR_MAP |
image_map { [MAP_PREFIX...] MAP_FILE [IMAGE_ATTRIB...] } |
bump_map { [MAP_PREFIX...] MAP_FILE [BUMP_ATTRIB...] } |
material_map { [MAP_PREFIX...] MAP_FILE [MATER_ATTRIB...] }
TEXTURE = texture { [TEXTURE_ITEMS...] }
USUAL_MODS = translate VECTOR |
rotate VECTOR |
scale VECTOR |
inverse |
TEXTURE |
COLOR_SPEC
SPHERE_BODY = VECTOR FLOAT |
SPHERE_IDENTIFIER
SPHERE = sphere { SPHERE_BODY [USUAL_MODS...] }
PLANE_BODY = VECTOR FLOAT |
PLANE_IDENTIFIER
PLANE = plane { PLANE_IDENTIFIER [USUAL_MODS...] }
HFILE_TYPE = gif STRING |
pot STRING |
tga STRING |
HFIELD_IDENTIFIER
HFIELD_MODS = USUAL_MODS |
water_level FLOAT
HFIELD = height_field { HFILE_TYPE [HFIELD_MODS...] }
TRI_BODY = VECTOR VECTOR VECTOR |
TRIANGLE_IDENTIFIER
TRIANGLE = triangle { TRI_BODY [USUAL_MODS...] }
SMO_TRI_BODY= VECTOR VECTOR VECTOR VECTOR VECTOR VECTOR |
SMOOTH_TRIANGLE_IDENTIFIER
SMO_TRIANGLE= smooth_triangle { SMO_TRI_BODY [USUAL_MODS...] }
QUAD_BODY = VECTOR VECTOR VECTOR FLOAT |
QUADRIC_IDENTIFIER
QUADRIC = quadric { QUAD_BODY [USUAL_MODS...] }
Note a POLY_N has M terms where M = (N+1)*(N+2)*(N+3)/6
POLY_N = "<" float_1 float_2... FLOAT_M ">" |
POLY_IDENTIFIER
POLY_MODS = USUAL_MODS | sturm
CUBIC = cubic { POLY_3 [POLY_MODS...] }
QUARTIC = quartic { POLY_4 [POLY_MODS...] }
POLY = poly { FLOAT POLY_N [POLY_MODS...] }
BI_BODY = FLOAT [FLOAT] FLOAT FLOAT VECTOR_1 VECTOR_2... VECTOR_16 |
BICUBIC_IDENTIFIER
BICUBIC = bicubic_patch { BI_BODY [USUAL_MODS...] }
BOX_BODY = VECTOR VECTOR |
BOX_IDENTIFIER
BOX = box { BOX_BODY [USUAL_MODS...] }
BLOB_ITEM = threshold FLOAT |
component FLOAT FLOAT VECTOR
BLOB_BODY = [BLOB_ITEM...] |
BLOB_IDENTIFIER
BLOB = blob { BLOB_BODY [POLY_MODS...] }
LIGHT_MODS = translate VECTOR |
rotate VECTOR |
scale VECTOR |
point_at VECTOR |
tightness FLOAT |
radius FLOAT |
falloff FLOAT |
spotlight |
COLOR_SPEC
LIGHT_BODY = VECTOR | LIGHT_IDENTIFIER
LIGHT_SOURCE= light_source { LIGHT_BODY [LIGHT_MODS..] }
SHAPE = LIGHT_SOURCE | SPHERE | PLANE | TRIANGLE | SMO_TRIANGLE |
QUADRIC | HFIELD | CUBIC | QUARTIC | POLY | BICUBIC |
BOX | BLOB | UNION | INTERSECTION | DIFFERENCE
CSG_BODY = SHAPE | CSG_IDENTIFIER
CSG_MODS = translate VECTOR |
rotate VECTOR |
scale VECTOR |
inverse
INTERSECTION= intersection { [CSG_BODY...] [CSG_MODS...] }
UNION = union { [CSG_BODY...] [CSG_MODS...] }
DIFFERENCE = difference { [CSG_BODY...] [CSG_MODS...] }
BOUNDED_BY = bounded_by { [SHAPE...] }
CLIPPED_BY = clipped_by { [SHAPE...] }
OBJ_BODY = SHAPE | OBJECT_IDENTIFIER
OBJ_MODS = USUAL_MODS | BOUNDED_BY | CLIPPED_BY | no_shadow
OBJECT = object { OBJ_BODY [OBJ_MODS...] }
COMP_MODS = CSG_MODS | BOUNDED_BY | CLIPPED_BY
COMP_BODY = COMPOSITE | OBJECT | COMP_IDENTIFIER
COMPOSITE = composite { COMP_BODY... [COMP_MODS...] }
CAMERA_BODY = location VECTOR |
direction VECTOR |
up VECTOR |
right VECTOR |
sky VECTOR |
look_at VECTOR |
translate VECTOR |
rotate VECTOR |
scale VECTOR |
CAMERA_IDENTIFIER
CAMERA = camera { [CAMERA_BODY...] }
FOG_BODY = COLOR_SPEC | FLOAT
FOG = fog { [FOG_BODY...] }
DECLARE_BODY= OBJECT | SHAPE | COMPOSITE | TEXTURE... | COLOR_SPEC |
CAMERA | VECTOR | FLOAT
DECLARE = declare IDENTIFIER "=" DECLARE_BODY
DEFAULT = default { TEXTURE }
FRAME_ITEM = FOG | DEFAULT | OBJECT | COMPOSITE | DECLARE | CAMERA |
max_trace_level FLOAT
FRAME = FRAME_ITEM...
