Change internal field TkFontAttributes.size from type integer to double. This causes less roundings overall in various font calculations.

Hopefully this fixes bug [434d294df], still to be confirmed, and makes Tk work again on modern Linux Mint/Fedora systems.

2 files changed, 21 insertions, 18 deletions

diff --git a/unix/tkUnixFont.c b/unix/tkUnixFont.c
index 0c663a3..b361e83 100644
--- a/unix/tkUnixFont.c
+++ b/unix/tkUnixFont.c
@@ -1535,7 +1535,7 @@ CreateClosestFont(
 	    continue;
 	}
 	IdentifySymbolEncodings(&got);
-	scalable = (got.fa.size == 0);
+	scalable = (got.fa.size == 0.0);
 	score = RankAttributes(&want, &got);
 	if (score < bestScore[scalable]) {
 	    bestIdx[scalable] = nameIdx;
@@ -1642,7 +1642,7 @@ InitFont(
     fmPtr->fixed = fixed;
 
     fontPtr->display = display;
-    fontPtr->pixelSize = TkFontGetPixels(tkwin, fa.fa.size);
+    fontPtr->pixelSize = (int)(TkFontGetPixels(tkwin, fa.fa.size) + 0.5);
     fontPtr->xa = fa.xa;
 
     fontPtr->numSubFonts = 1;
@@ -2453,7 +2453,7 @@ CanUseFallback(
     want.xa = fontPtr->xa;
 
     want.fa.family = Tk_GetUid(faceName);
-    want.fa.size = -fontPtr->pixelSize;
+    want.fa.size = (double)-fontPtr->pixelSize;
 
     hateFoundry = NULL;
     hateCharset = NULL;
@@ -2536,7 +2536,7 @@ CanUseFallback(
 	 * D. Rank each name and pick the best match.
 	 */
 
-	scalable = (got.fa.size == 0);
+	scalable = (got.fa.size == 0.0);
 	score = RankAttributes(&want, &got);
 	if (score < bestScore[scalable]) {
 	    bestIdx[scalable] = nameIdx;
@@ -2665,7 +2665,7 @@ RankAttributes(
 	penalty += 1000;
     }
 
-    if (gotPtr->fa.size == 0) {
+    if (gotPtr->fa.size == 0.0) {
 	/*
 	 * A scalable font is almost always acceptable, but the corresponding
 	 * bitmapped font would be better.
@@ -2679,14 +2679,14 @@ RankAttributes(
 	 * It's worse to be too large than to be too small.
 	 */
 
-	diff = (-gotPtr->fa.size - -wantPtr->fa.size);
+	diff = (int) (150 * (-gotPtr->fa.size - -wantPtr->fa.size));
 	if (diff > 0) {
 	    penalty += 600;
 	} else if (diff < 0) {
 	    penalty += 150;
 	    diff = -diff;
 	}
-	penalty += 150 * diff;
+	penalty += diff;
     }
     if (gotPtr->xa.charset != wantPtr->xa.charset) {
 	int i;
@@ -2773,7 +2773,7 @@ GetScreenFont(
 	}
 	*str = '\0';
 	sprintf(buf, "%.200s-%d-*-*-*-*-*%s", nameList[bestIdx[1]],
-		-wantPtr->fa.size, rest);
+		(int)(-wantPtr->fa.size+0.5), rest);
 	*str = '-';
 	fontStructPtr = XLoadQueryFont(display, buf);
 	bestScore[1] = INT_MAX;
diff --git a/unix/tkUnixRFont.c b/unix/tkUnixRFont.c
index 41cd096..a08b95f 100644
--- a/unix/tkUnixRFont.c
+++ b/unix/tkUnixRFont.c
@@ -170,18 +170,21 @@ GetTkFontAttributes(
 {
     const char *family = "Unknown";
     const char *const *familyPtr = &family;
-    int weight, slant, size, pxsize;
-    double ptsize;
+    int weight, slant, pxsize;
+    double size, ptsize;
 
     (void) XftPatternGetString(ftFont->pattern, XFT_FAMILY, 0, familyPtr);
     if (XftPatternGetDouble(ftFont->pattern, XFT_SIZE, 0,
 	    &ptsize) == XftResultMatch) {
-	size = (int) ptsize;
+	size = ptsize;
+    } else if (XftPatternGetDouble(ftFont->pattern, XFT_PIXEL_SIZE, 0,
+	    &ptsize) == XftResultMatch) {
+	size = -ptsize;
     } else if (XftPatternGetInteger(ftFont->pattern, XFT_PIXEL_SIZE, 0,
 	    &pxsize) == XftResultMatch) {
-	size = -pxsize;
+	size = (double)-pxsize;
     } else {
-	size = 12;
+	size = 12.0;
     }
     if (XftPatternGetInteger(ftFont->pattern, XFT_WEIGHT, 0,
 	    &weight) != XftResultMatch) {
@@ -194,7 +197,7 @@ GetTkFontAttributes(
 
 #if DEBUG_FONTSEL
     printf("family %s size %d weight %d slant %d\n",
-	    family, size, weight, slant);
+	    family, (int)size, weight, slant);
 #endif /* DEBUG_FONTSEL */
 
     faPtr->family = Tk_GetUid(family);
@@ -441,10 +444,10 @@ TkpGetFontFromAttributes(
     if (faPtr->family) {
 	XftPatternAddString(pattern, XFT_FAMILY, faPtr->family);
     }
-    if (faPtr->size > 0) {
-	XftPatternAddDouble(pattern, XFT_SIZE, (double)faPtr->size);
-    } else if (faPtr->size < 0) {
-	XftPatternAddInteger(pattern, XFT_PIXEL_SIZE, -faPtr->size);
+    if (faPtr->size > 0.0) {
+	XftPatternAddDouble(pattern, XFT_SIZE, faPtr->size);
+    } else if (faPtr->size < 0.0) {
+	XftPatternAddDouble(pattern, XFT_PIXEL_SIZE, -faPtr->size);
     } else {
 	XftPatternAddDouble(pattern, XFT_SIZE, 12.0);
     }