Files
smd_parametric_magazines_op…/fontmetrics.scad

287 lines
13 KiB
OpenSCAD

include <fontmetricsdata.scad>;
// begin MIT licensed code (c) 2018 Alexander Pruss
BOLD = 1;
ITALIC = 2;
CONDENSED = 32;
ASCENDER_TO_EM = 1510/2048; // mysterious factor to match OpenSCAD
METRICS_ADJUST = 1.0255; // this adjusts metrics a little bit to match OpenSCAD -- I don't know why this is needed
_XADVANCE = 1;
_LSB = 2;
_XMIN = 3;
_YMIN = 4;
_XMAX = 5;
_YMAX = 6;
_KERN = 7;
_FONTID = 0;
_ASCENDER = 1;
_DESCENDER = 2;
_LINEGAP = 3;
_UNITS_PER_EM = 4;
_GLYPHDATA = 5;
function fontScale(f) = 1 / (ASCENDER_TO_EM * f[_UNITS_PER_EM]);
function _isString(v) = v >= "";
function _isVector(v) = !(v>="") && len(v) != undef;
function _isFloat(v) = v+0 != undef;
function startswith(a,b,offset=0,position=0) =
len(a)-offset < len(b) ? false :
position >= len(b) ? true :
a[offset+position] != b[position] ? false :
startswith(a,b,offset=offset,position=position+1);
function findsubstring(a,b,position=0) =
len(a)-position < len(b) ? -1 :
startswith(a,b,offset=position) ? position :
findsubstring(a,b,position=position+1);
function style(a,b,n) =
findsubstring(a,b) >= 0 ? n : 0;
function substring(a,start,end=undef,soFar="") =
start >= len(a) || (end != undef && start >= end) ? soFar :
substring(a,start+1,end=end,soFar=str(soFar,a[start]));
function sublist(a,start,end=undef,soFar=[]) =
start >= len(a) || (end != undef && start >= end) ? soFar :
sublist(a,start+1,end=end,soFar=concat(soFar,[a[start]]));
function lowercaseChar(c) =
c < "A" || c > "Z" ? c :
chr(search(c,"ABCDEFGHIJKLMNOPQRSTUVWXYZ")[0]+97);
function lowercase(s,start=0,soFar="") =
start >= len(s) ? soFar :
lowercase(s,start=start+1,soFar=str(soFar,lowercaseChar(s[start])));
function splitstring(s,delimiter=" ",offset=0,lastStart=0,soFar=[]) =
len(s)==0 ? [] :
offset >= len(s) ? concat(soFar,[substring(s,lastStart,end=offset)]) :
s[offset] == delimiter ? splitstring(s,delimiter=delimiter,offset=offset+1,lastStart=offset+1,soFar=concat(soFar,[substring(s,lastStart,end=offset)])) :
splitstring(s,delimiter=delimiter,offset=offset+1,lastStart=lastStart,soFar=soFar);
function styleNumber(s) =
style(s, "bold", BOLD) +
style(s, "italic", ITALIC) +
style(s, "oblique", ITALIC) +
style(s, "condensed", CONDENSED);
function familyAndStyle(s) =
let(lc=lowercase(s),
n=findsubstring(lc,":style="))
n < 0 ? [s, 0] :
[substring(s,0,n), styleNumber(substring(lc,n+7))];
function findEntry(data, index) = data[search([index], data, 1, 0)[0]];
function findEntry_recursive(data, index, offset=0) =
offset >= len(data) ? undef :
data[offset][0] == index ? data[offset] :
findEntry(data, index, offset=offset+1);
function findFont(fonts, s) =
_isString(s) ? findEntry(fonts, familyAndStyle(s)) : s;
function getGlyphInfo(font,char) =
let(g=findEntry(font[_GLYPHDATA],char))
g == undef ? findEntry(font[_GLYPHDATA],"_") : g;
function measureWithFontAt(string,font,offset) =
let(g=getGlyphInfo(font,string[offset]))
g == undef ? 0 :
offset + 1 >= len(string) ? g[1] : // at end of string
let(kern=findEntry(g[_KERN], string[offset+1]))
kern == undef ? g[1] :
g[1] + kern[1];
function measureWithFont(string, font, offset=0, soFar=0) =
offset >= len(string) ? soFar :
measureWithFont(string,font,offset=offset+1,soFar=soFar+measureWithFontAt(string,font,offset));
function getOffsets(string, font, soFar=[0]) =
len(soFar) >= len(string)+1 ? soFar :
getOffsets(string, font, soFar=concat(soFar, [soFar[len(soFar)-1]+measureWithFontAt(string, font, offset=len(soFar)-1) ]));
function getScaledOffsets(string, font, size=10., spacing=1.) = spacing * size * fontScale(font) * getOffsets(string, font);
function measureText(text="", font="Liberation Sans", size=10., spacing=1., fonts=FONTS) =
let(f=findFont(FONTS, font))
spacing * size * fontScale(f) * measureWithFont(text, f);
function ascender(font="Liberation Sans", size=10., fonts=FONTS) =
let(f=findFont(fonts, font))
fontScale(f)*size*f[_ASCENDER]*METRICS_ADJUST;
function descender(font="Liberation Sans", size=10., fonts=FONTS) =
let(f=findFont(fonts, font))
fontScale(f)*size*f[_DESCENDER]*METRICS_ADJUST;
function linegap(font="Liberation Sans", size=10., fonts=FONTS) =
let(f=findFont(fonts, font))
fontScale(f)*size*f[_LINEGAP]*METRICS_ADJUST;
function verticalAdvance(font="Liberation Sans", size=10., fonts=FONTS) =
let(f=findFont(fonts, font))
fontScale(f)*size*(f[_ASCENDER]-f[_DESCENDER]+f[_LINEGAP])*METRICS_ADJUST;
function maximizeGlyphMetric(text,f,mult,index,offset=0,soFar=-1e100) =
len(text) == 0 ? 0 :
offset >= len(text) ? soFar :
maximizeGlyphMetric(text,f,mult,index,offset=offset+1,
soFar=max(soFar,mult*getGlyphInfo(f, text[offset])[index]));
function measureTextDescender(text="", size=10, font="Liberation Sans", fonts=FONTS) =
let(f=findFont(fonts, font))
-fontScale(f)*size*METRICS_ADJUST*maximizeGlyphMetric(text,f,-1,_YMIN);
function measureTextAscender(text="", size=10, font="Liberation Sans", fonts=FONTS) =
let(f=findFont(fonts, font))
fontScale(f)*size*METRICS_ADJUST*maximizeGlyphMetric(text,f,1,_YMAX);
function measureTextLeftBearing(text="", size=10, font="Liberation Sans", fonts=FONTS) =
len(text)==0 ? 0 : (
let(f=findFont(fonts,font),
g=getGlyphInfo(f, text[0]))
g == undef ? 0 : fontScale(f)*size*(METRICS_ADJUST*(g[_LSB]-g[_XMIN])+g[_XMIN]) );
function measureTextRightBearing(text="", size=10, font="Liberation Sans", fonts=FONTS) =
len(text)==0 ? 0 : (
let(f=findFont(fonts, font),
g=getGlyphInfo(findFont(fonts, font), text[len(text)-1]))
g == undef ? 0 : fontScale(f)*size*(METRICS_ADJUST*(g[_XMAX]-g[_XMIN])+g[_XMIN]-g[_XADVANCE]) );
//returns [leftX,bottomY,width,height]
function measureTextBounds(text="", size=10, font="Liberation Sans",spacing=1,valign="left",halign="baseline",fonts=FONTS) =
len(text)==0 ? [[0,0],[0,0]] : (
let(f=findFont(fonts,font),
w=measureText(text,size=size,font=f,spacing=spacing),
asc=measureTextAscender(text,size=size,font=f),
des=measureTextDescender(text,size=size,font=f),
lsb=measureTextLeftBearing(text,size=size,font=f),
rsb=measureTextRightBearing(text,size=size,font=f),
dx=halign=="right"?-w:
halign=="center"?-w/2:
0,
dy=valign=="top"?-asc:
valign=="bottom"?-des:
valign=="center"?-0.5*(asc+des):
0)
[[lsb+dx,des+dy],[w-lsb+rsb,asc-des]]);
module drawText(text="", size=10, font="Liberation Sans", halign="left", valign="baseline", spacing=1, fonts=FONTS) {
l = len(text);
if (l>0) {
sc = size < 20 ? size/20 : 1;
adjSize = size < 20 ? 20 : size;
f = findFont(fonts, font);
offsetScale = spacing * adjSize * fontScale(f);
offsets = getOffsets(text, f);
w = offsets[l];
dx = halign=="right" ? -w :
halign=="center" ? -w / 2 : 0;
dy = valign=="top" ? -measureTextAscender(text, size=size, font=font) :
valign=="bottom" ? -measureTextDescender(text, size=size, font=font) :
valign=="center" ? -0.5*(measureTextAscender(text, size=size, font=font)+measureTextDescender(text,size=size,font=font)) : 0;
scale(sc) {
for (i=[0:l-1]) {
translate([offsetScale*(dx+offsets[i]),dy]) text(findEntry(f[_GLYPHDATA],text[i])==undef?"_":text[i], size=adjSize, font=font);
}
}
}
}
function whereToSplit(offsets,width,pos=0) =
pos >= len(offsets)-1 ? pos : // shouldn't happen
offsets[pos+1] > width && pos > 0 ? pos :
whereToSplit(offsets,width,pos=pos+1);
// TODO: worry about splitting a kerning pair
function splitWord(word,f,width,size,spacing) =
let(o=getScaledOffsets(word,f,size=size,spacing=spacing),
i=whereToSplit(o,width),
w1=substring(word,0,i),
w2=substring(word,i))
[[w1,o[i]],[w2,o[len(word)]-o[i]]];
function splitWordsAsNeeded(words,f,firstWidth,width,size,spacing,offset=0) =
offset >= len(words) ? words :
words[offset][1] <= (offset==0 ? firstWidth : width) ? splitWordsAsNeeded(words,f,firstWidth,width,size,spacing,offset=offset+1) :
splitWordsAsNeeded(concat(sublist(words,0,offset),
splitWord(words[offset][0],f,(offset==0?firstWidth:width),size,spacing),sublist(words,offset+1)),f,firstWidth,width,size,spacing,offset=offset+1);
function addSizesToWords(words,f,firstWidth,width,size,spacing) =
let(wordsAndSizes=[for(i=[0:len(words)-1]) [words[i],measureText(words[i],font=f,size=size,spacing=spacing)]])
splitWordsAsNeeded(wordsAndSizes,f,firstWidth,width,size,spacing);
function wrapWordsToLines(words,space,width,x=0,offset=0,soFar=[],curLine=[]) =
offset >= len(words) ? (len(curLine)>0 ? concat(soFar,[curLine]) : soFar ) :
len(curLine) == 0 || x+words[offset][1] <= width ? wrapWordsToLines(words,space,width,x=x+words[offset][1]+space,offset=offset+1,soFar=soFar,curLine=concat(curLine,[words[offset]])) :
wrapWordsToLines(words,space,width,x=words[offset][1]+space,offset=offset+1,soFar=concat(soFar,[curLine]),curLine=[words[offset]]);
function splitParaToLines(words,f,indent,width,size,spacing) =
wrapWordsToLines(addSizesToWords(words,f,width-indent,width,size,spacing),measureText(" ",font=f,size=size,spacing=spacing),width,x=indent);
function formatLineNoJustify(words,x,y,space,offset=0,soFar=[]) =
offset>=len(words) ? soFar :
formatLineNoJustify(words,x+words[offset][1]+space,y,space,offset=offset+1,soFar=concat(soFar,[[[x,y],words[offset][0]]]));
function totalWidthWords(words,space=0,offset=0,soFar=0) =
offset>=len(words) ? soFar :
totalWidthWords(words,space,offset=offset+1,soFar=soFar + words[offset][1] + (offset>0?space:0));
function formatLine(words,x,y,space,width,halign) =
halign=="justify" ? formatLineNoJustify(words,x,y,len(words)<=1 ? 0 : (width-totalWidthWords(words))/(len(words)-1)) :
halign=="right" ? formatLineNoJustify(words,x-totalWidthWords(words,space=space),y,space) :
halign=="center" ? formatLineNoJustify(words,x-totalWidthWords(words,space=space)/2,y,space) :
formatLineNoJustify(words,x,y,space);
function formatParaLines(lines,indent,space,width,b2b,halign) = [for(i=[0:len(lines)-1]) for(w=formatLine(lines[i],i==0?indent:0,-i*b2b,space,width,halign=="justify" && i+1==len(lines) ? "left" : halign )) w];
function lastYInPara(para) =
len(para) == 0 ? 0 : para[len(para)-1][0][1];
function shiftPara(delta,para) =
len(para) == 0 ? [] :
[for(i=[0:len(para)-1]) [delta+para[i][0],para[i][1]]];
function joinFormattedParas(paras,b2b,y=0,offset=0,soFar=[]) =
offset >= len(paras) ? soFar :
joinFormattedParas(paras,b2b,y=y-b2b+lastYInPara(paras[offset]),offset=offset+1,soFar=concat(soFar,shiftPara([0,y],paras[offset])));
function formatParagraphText(s,f,indent,width,size,spacing,b2b,halign) =
let(words=splitstring(s))
len(words)==0 ? [] :
let(lines=splitParaToLines(words,f,indent,width,size,spacing))
formatParaLines(lines,indent,measureText(" ",size=size,spacing=spacing,font=f),width,b2b,halign);
function wrapText(s,font="Liberation Sans",size=10,spacing=1,linespacing=1,indent=0,width=800,halign="left",fonts=FONTS) =
let(paras = splitstring(s,delimiter="\n"),
f = findFont(FONTS,font),
b2b = verticalAdvance(f,size=size)*linespacing,
formattedParas = [ for(p=paras) formatParagraphText(p,f,indent,width,size,spacing,b2b,halign) ])
joinFormattedParas(formattedParas,b2b);
function measureWrappedTextBounds(s,font="Liberation Sans",size=10,spacing=1,linespacing=1,indent=0,width=800,halign="left",fonts=FONTS) =
let(f=findFont(fonts,font),
formatted=wrapText(s,font=font,size=size,spacing=spacing,linespacing=linespacing,indent=indent,width=width,halign=halign,fonts=FONTS),
corners=[for(w=formatted) let(b=measureTextBounds(w[1],font=font,size=size,spacing=spacing,fonts=FONTS)) for(xy=[w[0]+b[0],w[0]+b[0]+b[1]]) xy],
xCorners=[for(c=corners) c[0]],
yCorners=[for(c=corners) c[1]],
x0=min(xCorners),
y0=min(yCorners))
[[x0,y0],[max(xCorners)-x0,max(yCorners)-y0]];
module drawWrappedText(s,font="Liberation Sans",size=10,spacing=1,linespacing=1,indent=0,width=800,halign="left",fonts=FONTS) {
f=findFont(fonts,font);
formatted = wrapText(s,font=f,size=size,spacing=spacing,indent=indent,width=width,halign=halign,fonts=fonts);
for(w=formatted)
translate(w[0]) drawText(w[1],font=font,size=size,spacing=spacing,fonts=FONTS); /**/
}