GGParseInImpl.mesa
Copyright © 1986 by Xerox Corporation. All rights reserved.
Last edited by Bier on January 6, 1986 11:33:00 pm PST
Contents: Routines for reading gargoyle data structures from a stream. Stolen from Solidviews Solidmodeler TFI3d.mesa.
DIRECTORY
Convert, GGBasicTypes, GGParseIn, Imager, ImagerColor, ImagerTransformation, IO, RefText, Rope;
GGParseInImpl:
CEDAR
PROGRAM
IMPORTS Convert, Imager, ImagerColor, ImagerTransformation, IO, RefText, Rope
EXPORTS GGParseIn =
BEGIN
RopeNotOnTop: PUBLIC SIGNAL [position: NAT, wasThere: Rope.ROPE, notThere: Rope.ROPE] = CODE;
Color: TYPE = Imager.Color;
Point: TYPE = GGBasicTypes.Point;
ReadBlank:
PUBLIC
PROC [f:
IO.
STREAM] = {
Reads, <SPACE>'s, <CR>'s, and <TAB>'s until something else is encountered. Doesn't mind if no white space characters are found. Treats comments as white space.
[] ← IO.SkipWhitespace[f, TRUE];
};
ReadWhiteSpace:
PUBLIC
PROC [f:
IO.
STREAM] = {
Reads, <SPACE>'s, <CR>'s, and <TAB>'s until something else is encountered. Signals RopeNotOnTop if no white space characters are found.
WhiteSpaceProc:
SAFE
PROC [char:
CHAR]
RETURNS [
IO.CharClass] =
TRUSTED {
SELECT char
FROM
IO.TAB => RETURN [other];
IO.CR =>RETURN [other];
IO.SP => RETURN [other];
ENDCASE => RETURN [break];
};
whiteSpace: Rope.ROPE;
end: BOOL ← FALSE;
[whiteSpace,
----] ←
IO.GetTokenRope[f, WhiteSpaceProc
!IO.EndOfStream => {end ← TRUE; CONTINUE}];
IF end OR Rope.Size[whiteSpace] = 0 THEN SIGNAL RopeNotOnTop[IO.GetIndex[f], "null", "<whitespace>"];
};
ReadHorizontalBlank:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [good:
BOOL] = {
Reads <SPACE>'s, and <TABS>'s until something else is encountered. Returns good = FALSE if a CR is encountered before anything else
HorizontalBlankProc:
SAFE
PROC [char:
CHAR]
RETURNS [
IO.CharClass] =
TRUSTED {
SELECT char
FROM
IO.TAB, IO.SP => RETURN [other];
ENDCASE => RETURN [break];
};
whiteSpace: Rope.ROPE;
c: CHAR;
end: BOOL ← FALSE;
good ← TRUE;
[whiteSpace,
----] ←
IO.GetTokenRope[f, HorizontalBlankProc
!IO.EndOfStream => {end ← TRUE; CONTINUE}];
IF end THEN {good ← FALSE; RETURN};
c ← Rope.Fetch[whiteSpace, 0];
SELECT c
FROM
IO.CR => {good ← FALSE; RETURN};
IO.TAB, IO.SP => {good ← TRUE; RETURN};
ENDCASE => {good ← TRUE; IO.Backup[f, c]; RETURN};
};
ReadWord:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [word: Rope.
ROPE] = {
Used to read in a rope which is data.
WordBreakProc:
SAFE
PROC [char:
CHAR]
RETURNS [
IO.CharClass] =
CHECKED {
SELECT char
FROM
IO.TAB => RETURN [break];
IO.CR =>RETURN [break];
IO.SP => RETURN [break];
', => RETURN [break];
'] => RETURN [break];
') => RETURN [break];
ENDCASE => RETURN [other];
};
[word,
----] ←
IO.GetTokenRope[f, WordBreakProc
!IO.EndOfStream => {word ← NIL; CONTINUE}];
};
ReadColorToken:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [word: Rope.
ROPE] = {
Reads a rope until <SPACE>, <CR> or <TAB> are encountered.
ColorBreakProc:
SAFE
PROC [char:
CHAR]
RETURNS [
IO.CharClass] =
CHECKED {
SELECT char
FROM
IO.TAB => RETURN [break];
IO.CR =>RETURN [break];
IO.SP => RETURN [break];
ENDCASE => RETURN [other];
};
[word,
----] ←
IO.GetTokenRope[f, ColorBreakProc
!IO.EndOfStream => {word ← NIL; CONTINUE}];
};
ReadBlankAndWord:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [word: Rope.
ROPE] = {
A convenience function. Equivalent to ReadBlank[f]; word ← ReadWord[f];
ReadBlank[f];
word ← ReadWord[f];
};
ReadBlankAndColor:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [word: Rope.
ROPE] = {
ReadBlank[f];
word ← ReadColorToken[f];
};
ReadRope:
PUBLIC
PROC [f:
IO.
STREAM, rope: Rope.
ROPE] = {
Removes the given rope from the top of the stream. Used to remove formatting words and phrases from 3d files. We are not interested in these strings but only in the data in between them.
Signals RopeNotOnTop if some other rope is on top.
c: CHAR;
endofstream: BOOL ← FALSE;
FOR i:
INT
IN[1..Rope.Length[rope]]
DO
c ←
IO.GetChar[f
! IO.EndOfStream => {endofstream ← TRUE; CONTINUE}];
IF endofstream
THEN
SIGNAL RopeNotOnTop [IO.GetIndex[f], NIL, rope];
IF
NOT c = Rope.Fetch[rope,i-1]
THEN
SIGNAL RopeNotOnTop [IO.GetIndex[f], Rope.FromChar[c], rope];
ENDLOOP;
};
ReadBlankAndRope:
PUBLIC
PROC [f:
IO.
STREAM, rope: Rope.
ROPE] = {
ReadBlank[f];
ReadRope[f, rope];
};
ReadNAT:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [n:
NAT] = {
Reads digits up to the next ], <CR>, <SPACE>. Leaves these terminators on the stream.
NATBreakProc:
SAFE
PROC [char:
CHAR]
RETURNS [
IO.CharClass] =
TRUSTED {
SELECT char
FROM
'], IO.CR, IO.SP, '., ',, ': => RETURN [break];
ENDCASE => RETURN [other];
};
end: BOOL ← FALSE;
intRope: Rope.ROPE;
[intRope,
----] ←
IO.GetTokenRope[f, NATBreakProc
!IO.EndOfStream => {end ← TRUE; CONTINUE}];
IF end THEN {n ← 1; RETURN};
n ← Convert.IntFromRope[intRope];
};
ReadBlankAndNAT:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [n:
NAT] = {
A convenience function. Equivalent to ReadBlank[f]; n ← ReadNAT[f];
ReadBlank[f];
n ← ReadNAT[f];
};
ReadColor:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [color: Color] = {
s: IO.STREAM;
r, g, b: REAL;
word: Rope.ROPE ← ReadBlankAndColor[f];
IF Rope.Equal[word, "none"] THEN RETURN[NIL];
s ← IO.RIS[word, colorStream];
ReadChar[s, '[];
r ← ReadBlankAndReal[s];
ReadChar[s, ',];
g ← ReadBlankAndReal[s];
ReadChar[s, ',];
b ← ReadBlankAndReal[s];
ReadChar[s, ']];
color ← ImagerColor.ColorFromRGB[[r, g, b]];
IF ImagerColor.GrayFromColor[NARROW[color]]=1.0 THEN color ← Imager.black; -- "process black"
}; -- end of ReadColor
ReadStrokeEnd:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [strokeEnd: Imager.StrokeEnd] = {
endName: Rope.ROPE ← ReadBlankAndWord[f];
SELECT TRUE FROM
Rope.Equal[endName, "square", TRUE] => strokeEnd ← square;
Rope.Equal[endName, "butt", TRUE] => strokeEnd ← butt;
Rope.Equal[endName, "round", TRUE] => strokeEnd ← round;
ENDCASE => ERROR;
};
ReadPoint:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [point: Point] = {
Assumes the next rope on the stream will be of the form "[<real1>,<real2>]".
ReadRope[f, "["];
point.x ← ReadBlankAndReal[f];
ReadRope[f, ","];
point.y ← ReadBlankAndReal[f];
ReadRope[f, "]"];
};
ReadChar:
PUBLIC
PROC [f:
IO.
STREAM, c:
CHAR] = {
streamC: CHAR ← IO.GetChar[f];
IF NOT c = streamC THEN SIGNAL RopeNotOnTop[IO.GetIndex[f], Rope.FromChar[streamC], Rope.FromChar[c]];
};
ReadKeyWord:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [keyWord: Rope.
ROPE, good:
BOOL] = {
Reads a rope until a ':' or <CR> are encountered. If CR is encountered first, then good is FALSE since ":" is expected after a keyword.
KeyWordBreakProc:
SAFE
PROC [char:
CHAR]
RETURNS [
IO.CharClass] =
CHECKED {
SELECT char
FROM
IO.CR =>RETURN [break];
': => RETURN [break];
ENDCASE => RETURN [other];
};
end: BOOL ← FALSE;
nextChar: Rope.ROPE;
[keyWord,
----] ←
IO.GetTokenRope[f, KeyWordBreakProc
!IO.EndOfStream => {end ← TRUE; CONTINUE}];
IF end THEN {good ← FALSE; keyWord ← NIL; RETURN};
[nextChar,
----] ←
IO.GetTokenRope[f, KeyWordBreakProc
!IO.EndOfStream => {end ← TRUE; CONTINUE}];
IF end THEN {good ← FALSE; RETURN};
good ← Rope.Equal[nextChar, ":", TRUE];
};
ReadLine:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [line: Rope.
ROPE] = {
Reads a rope UNTIL <CR> is encountered.
LineBreakProc:
SAFE
PROC [char:
CHAR]
RETURNS [
IO.CharClass] =
CHECKED {
SELECT char
FROM
IO.CR =>RETURN [break];
ENDCASE => RETURN [other];
};
end: BOOL ← FALSE;
[line,
----] ←
IO.GetTokenRope[f, LineBreakProc
!IO.EndOfStream => {end ← TRUE; CONTINUE}];
IF end THEN {line ← NIL; RETURN};
[----, ----] ← IO.GetTokenRope[f, LineBreakProc]; -- remove <CR>
};
ReadReal:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [r:
REAL] = {
Reads digits up to the next ), ], <CR>, <SPACE> or <COMMA>. Leaves these terminators on the stream.
RealBreakProc:
SAFE
PROC [char:
CHAR]
RETURNS [
IO.CharClass] =
TRUSTED {
SELECT char
FROM
'), '], ', => RETURN [break];
IO.CR =>RETURN [break];
IO.SP => RETURN [break];
ENDCASE => RETURN [other];
};
realText, buffer: REF TEXT;
end: BOOL ← FALSE;
buffer ← RefText.ObtainScratch[50];
[realText,
----] ←
IO.GetToken[f, RealBreakProc, buffer
!IO.EndOfStream => {end ← TRUE; CONTINUE}];
IF end THEN {r ← 0.0; RETURN};
IF RefText.Find[realText, ".", 0, FALSE] = -1 THEN realText ← RefText.Append[realText, ".0"];
r ← Convert.RealFromRope[RefText.TrustTextAsRope[realText]];
RefText.ReleaseScratch[buffer];
};
ReadBlankAndReal:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [r:
REAL] = {
A convenience function. Equivalent to ReadBlank[f]; r ← ReadReal[f];
ReadBlank[f];
r ← ReadReal[f];
};
ReadBOOL:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [truth:
BOOL, good:
BOOL] = {
Tries to read TRUE or FALSE from the stream. If it encounters another word, good = FALSE;
BoolBreakProc:
SAFE
PROC [char:
CHAR]
RETURNS [
IO.CharClass] =
TRUSTED {
SELECT char
FROM
'], IO.CR, IO.SP, '., ', => RETURN [break];
ENDCASE => RETURN [other];
};
end: BOOL ← FALSE;
boolRope: Rope.ROPE;
[boolRope,
----] ←
IO.GetTokenRope[f, BoolBreakProc
!IO.EndOfStream => {end ← TRUE; CONTINUE}];
IF end THEN {good ← FALSE; truth ← FALSE; RETURN};
good ← TRUE;
IF Rope.Equal[boolRope, "TRUE", TRUE] THEN truth ← TRUE
ELSE
IF Rope.Equal[boolRope, "FALSE",
TRUE]
THEN truth ←
FALSE
ELSE {truth ← FALSE; good ← FALSE};
};
ReadListOfRope:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [ropeList:
LIST
OF Rope.
ROPE] = {
RopesOnOneLineOrParenProc:
SAFE
PROC [char:
CHAR]
RETURNS [
IO.CharClass] =
CHECKED {
SELECT char
FROM
IO.CR, ') =>RETURN [break];
IO.SP, IO.TAB, ', , '; => RETURN [sepr];
ENDCASE => RETURN [other];
};
rope: Rope.ROPE;
end: BOOL ← FALSE;
ropeList ← NIL;
WHILE
TRUE
DO
[rope,
----] ←
IO.GetTokenRope[f,
RopesOnOneLineOrParenProc
!IO.EndOfStream => {end ← TRUE; CONTINUE}];
IF end OR rope = NIL THEN RETURN;
IF Rope.Equal[rope, Rope.FromChar[IO.CR]] THEN RETURN;
IF Rope.Equal[rope, Rope.FromChar[')]]
THEN {
f.Backup[')];
RETURN;
};
ropeList ← AppendRopeToRopeList[rope, ropeList];
ENDLOOP;
};
ReadTransformation:
PUBLIC
PROC [f:
IO.
STREAM]
RETURNS [transform: ImagerTransformation.Transformation] = {
a, b, c, d, e, g: REAL;
ReadBlankAndRope[f, "["];
a ← ReadBlankAndReal[f];
b ← ReadBlankAndReal[f];
c ← ReadBlankAndReal[f];
d ← ReadBlankAndReal[f];
e ← ReadBlankAndReal[f];
g ← ReadBlankAndReal[f];
ReadBlankAndRope[f, "]"];
transform ← ImagerTransformation.Create[a, b, c, d, e, g];
};
AppendRopeToRopeList:
PROC [rope: Rope.
ROPE, list:
LIST
OF Rope.
ROPE]
RETURNS [
LIST
OF Rope.
ROPE] = {
A copy of List.Nconc1 for LIST OF Rope.ROPE instead of LIST OF REF ANY
z: LIST OF Rope.ROPE ← list;
IF z = NIL THEN RETURN[CONS[rope,NIL]];
UNTIL z.rest = NIL DO z ← z.rest; ENDLOOP;
z.rest ← CONS[rope,NIL];
RETURN[list];
};
colorStream: IO.STREAM;
realNumberStream: IO.STREAM;
Init:
PROC [] = {
realNumberStream ← IO.TIS["This string is longer than any real number is likely to be."];
colorStream ← IO.RIS["This string is longer than any color is likely to be."];
};
END.