- font system fixes.

source/common/fonts/font.cpp

@@ -656,6 +656,10 @@ int FFont::GetLuminosity (uint32_t *colorsused, TArray<double> &Luminosity, int*
 
 int FFont::GetColorTranslation (EColorRange range, PalEntry *color) const
 {
+	// Single pic fonts do not set up their translation table and must always return 0.
+	if (Translations.Size() == 0) return 0;
+	assert(Translations.Size() == NumTextColors);
+
 	if (noTranslate)
 	{
 		PalEntry retcolor = PalEntry(255, 255, 255, 255);

source/common/fonts/specialfont.cpp

@@ -141,6 +141,17 @@ void FSpecialFont::LoadTranslations()
 {
 	FFont::LoadTranslations();
 
+	bool empty = true;
+	for (auto& c : Chars)
+	{
+		if (c.OriginalPic != nullptr)
+		{
+			empty = false;
+			break;
+		}
+	}
+	if (empty) return; // Font has no characters.
+
 	bool needsnotrans = false;
 	// exclude the non-translated colors from the translation calculation
 	for (int i = 0; i < 256; i++)

source/common/fonts/v_font.cpp

@@ -714,13 +714,16 @@ static void CalcDefaultTranslation(FFont* base, int index)
 		{
 			int index = int(lum * 255);
 			remap[index] = GPalette.BaseColors[i];
+			remap[index].a = 255;
 		}
 	}
 
 	// todo: fill the gaps.
-	remap[0] = 0;
+	//remap[0] = 0;
 	int lowindex = 0;
-	int highindex = 1;
+	while (lowindex < 255 && remap[lowindex].a == 0) lowindex++;
+	lowindex++;
+	int highindex = lowindex + 1;
 
 	while (lowindex < 255)
 	{