Rename m_ranges to m_invalid_glyphs

Rename containsGlyph to isValidGlyph
Change the approach to checking if a font can handle a glyph. The original approach was to pass the valid glyph range to the constructor. When it's not found by ImGui we call AddGlyph where we check if it's valid for the font. In the event where ImGui couldn't handle a glyph that was defined as valid in the constructor, that led to constant re-baking of fonts. The new approach is to change m_ranges (which used to contain valid glyph ranges) to m_invalid_glyphs, which contains only invalid glyphs that we tried to add to the font but failed. The next time AddGlyph is called, we skip the font since it's unable to handle the glyph.

src/PiGui.cpp

@@ -138,7 +138,7 @@ void PiGui::AddGlyph(ImFont *font, unsigned short glyph)
 	}
 	PiFont &pifont = pifont_iter->second;
 	for (PiFace &face : pifont.faces()) {
-		if (face.containsGlyph(glyph)) {
+		if (face.isValidGlyph(glyph)) {
 			face.addGlyph(glyph);
 			m_should_bake_fonts = true;
 			return;
@@ -743,9 +743,9 @@ PiGui::PiGui() :
 	m_should_bake_fonts(true)
 {
 	PiFont uiheading("orbiteer", {
-									 PiFace("DejaVuSans.ttf", /*18.0/20.0*/ 1.2, { { 0x400, 0x4ff }, { 0x500, 0x527 } }), PiFace("wqy-microhei.ttc", 1.0, { { 0x4e00, 0x9fff }, { 0x3400, 0x4dff } }), PiFace("Orbiteer-Bold.ttf", 1.0, { { 0, 0xffff } }) // imgui only supports 0xffff, not 0x10ffff
+									 PiFace("DejaVuSans.ttf", /*18.0/20.0*/ 1.2), PiFace("wqy-microhei.ttc", 1.0), PiFace("Orbiteer-Bold.ttf", 1.0) // imgui only supports 0xffff, not 0x10ffff
 								 });
-	PiFont guifont("pionillium", { PiFace("DejaVuSans.ttf", 13.0 / 14.0, { { 0x400, 0x4ff }, { 0x500, 0x527 } }), PiFace("wqy-microhei.ttc", 1.0, { { 0x4e00, 0x9fff }, { 0x3400, 0x4dff } }), PiFace("PionilliumText22L-Medium.ttf", 1.0, { { 0, 0xffff } }) });
+	PiFont guifont("pionillium", { PiFace("DejaVuSans.ttf", 13.0 / 14.0), PiFace("wqy-microhei.ttc", 1.0), PiFace("PionilliumText22L-Medium.ttf", 1.0) });
 	AddFontDefinition(uiheading);
 	AddFontDefinition(guifont);
 
@@ -759,14 +759,10 @@ PiGui::PiGui() :
 	GetFont("pionillium", 14);
 };
 
-const bool PiFace::containsGlyph(unsigned short glyph) const
+const bool PiFace::isValidGlyph(unsigned short glyph) const
 {
 	PROFILE_SCOPED()
-	for (auto range : m_ranges) {
-		if (range.first <= glyph && glyph <= range.second)
-			return true;
-	}
-	return false;
+	return (m_invalid_glyphs.count(glyph) == 0);
 }
 
 void PiFace::addGlyph(unsigned short glyph)
@@ -776,6 +772,7 @@ void PiFace::addGlyph(unsigned short glyph)
 	for (auto &range : m_used_ranges) {
 		if (range.first <= glyph && glyph <= range.second) {
 			// Output(" - already added, not adding again\n");
+			m_invalid_glyphs.insert(glyph); //if already added it once and trying to add it again, it's invalid
 			return;
 		}
 	}

src/PiGui.h

@@ -8,28 +8,25 @@
 #include "RefCounted.h"
 #include "graphics/opengl/RendererGL.h"
 #include "imgui/imgui.h"
+#include <unordered_set>
 
 class PiFace {
 	friend class PiGui; // need acces to some private data
 	std::string m_ttfname; // only the ttf name, it is automatically sought in data/fonts/
 	float m_sizefactor; // the requested pixelsize is multiplied by this factor
-	std::vector<std::pair<unsigned short, unsigned short>> m_ranges;
+	std::unordered_set<unsigned short> m_invalid_glyphs;
 	mutable std::vector<std::pair<unsigned short, unsigned short>> m_used_ranges;
 	ImVector<ImWchar> m_imgui_ranges;
 
 public:
 	PiFace(const std::string &ttfname, float sizefactor) :
 		m_ttfname(ttfname),
 		m_sizefactor(sizefactor) {}
-	PiFace(const std::string &ttfname, float sizefactor, const std::vector<std::pair<unsigned short, unsigned short>> &ranges) :
-		m_ttfname(ttfname),
-		m_sizefactor(sizefactor),
-		m_ranges(ranges) {}
 	const std::string &ttfname() const { return m_ttfname; }
 	const float sizefactor() const { return m_sizefactor; }
-	const std::vector<std::pair<unsigned short, unsigned short>> &ranges() const { return m_ranges; }
+	//std::unordered_map<unsigned short, unsigned short> &invalid_glyphs() const { return m_invalid_glyphs; }
 	const std::vector<std::pair<unsigned short, unsigned short>> &used_ranges() const { return m_used_ranges; }
-	const bool containsGlyph(unsigned short glyph) const;
+	const bool isValidGlyph(unsigned short glyph) const;
 	void addGlyph(unsigned short glyph);
 	void sortUsedRanges() const;
 };