commit ccbac353eaea45f8480523caba9c0697cb3eacb2
Author: Georg Baum <[email protected]>
Date: Sun Jul 12 18:36:19 2015 +0200
Fix Length::inBP()
Length::inBP() returned the wrong values for most units. I guess that this
was
caused by the default case in the switch statement: It did probably exist
before the other units were added.
inBP() is now correct for all units except the font dependent ones em, ex
and
mu and the percent units: For these only approximate values are returned,
since not all needed information is available.
diff --git a/src/Length.cpp b/src/Length.cpp
index ec89e5b..35f6b0c 100644
--- a/src/Length.cpp
+++ b/src/Length.cpp
@@ -200,9 +200,9 @@ int Length::inPixels(int text_width, int em_width_base)
const
// DPI setting for monitor: pixels/inch
double const dpi = lyxrc.dpi; // screen resolution [pixels/inch]
- double const em_width = (em_width_base > 0)
- ? em_width_base
- : 10*(dpi/72.27)*zoom;
+ double const em_width_in = (em_width_base > 0)
+ ? em_width_base / (zoom * dpi)
+ : 10.0/72.27;
// A different estimate for em_width is
// theFontMetrics(FontInfo(sane_font)).em()
// but this estimate might not be more accurate as the screen font
@@ -212,52 +212,53 @@ int Length::inPixels(int text_width, int em_width_base)
const
// between lengths and font sizes on the screen
// is the same as on paper.
+ double const text_width_in = text_width / (zoom * dpi);
+ double const result = zoom * dpi * inInch(text_width_in, em_width_in);
+ return static_cast<int>(result + ((result >= 0) ? 0.5 : -0.5));
+}
+
+
+double Length::inInch(double text_width, double em_width) const
+{
double result = 0.0;
switch (unit_) {
case Length::SP:
// Scaled point: sp = 1/65536 pt
- result = zoom * dpi * val_
- / (72.27 * 65536); // 4736286.7
+ result = val_ / (72.27 * 65536); // 4736286.7
break;
case Length::PT:
// Point: 1 pt = 1/72.27 inch
- result = zoom * dpi * val_
- / 72.27; // 72.27
+ result = val_ / 72.27; // 72.27
break;
case Length::BP:
// Big point: 1 bp = 1/72 inch
- result = zoom * dpi * val_
- / 72; // 72
+ result = val_ / 72; // 72
break;
case Length::DD:
// Didot: 1157dd = 1238 pt?
- result = zoom * dpi * val_
- / (72.27 / (0.376 * 2.845)); // 67.559735
+ result = val_ / (72.27 / (0.376 * 2.845)); // 67.559735
break;
case Length::MM:
// Millimeter: 1 mm = 1/25.4 inch
- result = zoom * dpi * val_
- / 25.4; // 25.4
+ result = val_ / 25.4; // 25.4
break;
case Length::PC:
// Pica: 1 pc = 12 pt
- result = zoom * dpi * val_
- / (72.27 / 12); // 6.0225
+ result = val_ / (72.27 / 12); // 6.0225
break;
case Length::CC:
// Cicero: 1 cc = 12 dd
- result = zoom * dpi * val_
+ result = val_
/ (72.27 / (12 * 0.376 * 2.845)); // 5.6299779
break;
case Length::CM:
// Centimeter: 1 cm = 1/2.54 inch
- result = zoom * dpi * val_
- / 2.54; // 2.54
+ result = val_ / 2.54; // 2.54
break;
case Length::IN:
// Inch
- result = zoom * dpi * val_;
+ result = val_;
break;
case Length::EX:
// Ex: The height of an "x"
@@ -291,7 +292,7 @@ int Length::inPixels(int text_width, int em_width_base)
const
result = 0; // this cannot happen
break;
}
- return static_cast<int>(result + ((result >= 0) ? 0.5 : -0.5));
+ return result;
}
@@ -305,25 +306,10 @@ int Length::inBP() const
{
// return any Length value as a one with
// the PostScript point, called bp (big points)
- double result = 0.0;
- switch (unit_) {
- case Length::CM:
- // 1bp = 0.2835cm
- result = val_ * 28.346;
- break;
- case Length::MM:
- // 1bp = 0.02835mm
- result = val_ * 2.8346;
- break;
- case Length::IN:
- // 1pt = 1/72in
- result = val_ * 72.0;
- break;
- default:
- // no other than bp possible
- result = val_;
- break;
- }
+
+ double const text_width_in = 210.0 / 2.54; // assume A4
+ double const em_width_in = 10.0 / 72.27;
+ double result = 72.0 * inInch(text_width_in, em_width_in);
return static_cast<int>(result + 0.5);
}
diff --git a/src/Length.h b/src/Length.h
index ef17bac..2a8f064 100644
--- a/src/Length.h
+++ b/src/Length.h
@@ -102,6 +102,7 @@ public:
*/
int inPixels(MetricsBase const &) const;
/// return the value in Big Postscript points.
+ /// Caution: Inaccurate for em, ex, mu and percent units.
int inBP() const;
/// return the default unit (centimeter or inch)
@@ -110,6 +111,8 @@ public:
friend bool isValidLength(std::string const & data, Length * result);
private:
+ /// Convert value to inch for text width and em width given in inch
+ double inInch(double text_width, double em_width) const;
///
double val_;
///
diff --git a/src/tests/regfiles/Length b/src/tests/regfiles/Length
index 581ec15..65dfd10 100644
--- a/src/tests/regfiles/Length
+++ b/src/tests/regfiles/Length
@@ -18,21 +18,21 @@
12881
0
2342
-2342
-66386
-2342
-2342
-2342
+29951
+66387
+2496
+23333
+10045
168624
6639
-2342
-2342
-2342
-2342
-2342
-2342
-2342
-2342
-2342
-2342
-2342
+1296
+27999
+2333
+0
+139414
+139414
+237003
+139414
+249132
+306710
+0
