From: Mikko Rasa <tdb@tdb.fi>
Date: Wed, 12 Nov 2014 09:00:38 +0000 (+0200)
Subject: Use triangle strips for creating strings
X-Git-Url: http://git.tdb.fi/?a=commitdiff_plain;h=6327ae3d1f8a976f839ce333500c1643f9965fca;p=libs%2Fgl.git

Use triangle strips for creating strings

Quads are not supported by modern OpenGL.
---

diff --git a/source/font.cpp b/source/font.cpp
index 1005609e..6780f5fa 100644
--- a/source/font.cpp
+++ b/source/font.cpp
@@ -74,7 +74,6 @@ void Font::build_string(const string &str, StringCodec::Decoder &dec, PrimitiveB
 {
 	MatrixStack::Push push_mtx(bld.matrix());
 
-	bld.begin(QUADS);
 	unsigned prev = 0;
 	for(string::const_iterator i=str.begin(); i!=str.end();)
 	{
@@ -86,22 +85,23 @@ void Font::build_string(const string &str, StringCodec::Decoder &dec, PrimitiveB
 		if(prev)
 			bld.matrix() *= Matrix::translation(get_glyph_advance(prev, c), 0, 0);
 
-		create_glyph_vertices(j->second, bld);
+		create_glyph_quad(j->second, bld);
 		prev = c;
 	}
-	bld.end();
 }
 
-void Font::create_glyph_vertices(const Glyph &glyph, VertexBuilder &bld) const
+void Font::create_glyph_quad(const Glyph &glyph, PrimitiveBuilder &bld) const
 {
+	bld.begin(TRIANGLE_STRIP);
+	bld.texcoord(glyph.x1, glyph.y2);
+	bld.vertex(glyph.off_x, glyph.off_y+glyph.h);
 	bld.texcoord(glyph.x1, glyph.y1);
 	bld.vertex(glyph.off_x, glyph.off_y);
-	bld.texcoord(glyph.x2, glyph.y1);
-	bld.vertex(glyph.off_x+glyph.w, glyph.off_y);
 	bld.texcoord(glyph.x2, glyph.y2);
 	bld.vertex(glyph.off_x+glyph.w, glyph.off_y+glyph.h);
-	bld.texcoord(glyph.x1, glyph.y2);
-	bld.vertex(glyph.off_x, glyph.off_y+glyph.h);
+	bld.texcoord(glyph.x2, glyph.y1);
+	bld.vertex(glyph.off_x+glyph.w, glyph.off_y);
+	bld.end();
 }
 
 float Font::get_glyph_advance(unsigned code, unsigned next) const
diff --git a/source/font.h b/source/font.h
index bb8bd0a2..efef8351 100644
--- a/source/font.h
+++ b/source/font.h
@@ -127,7 +127,7 @@ public:
 	{ return build_string<StringCodec::Utf8>(str, pb); }
 
 private:
-	void create_glyph_vertices(const Glyph &, VertexBuilder &) const;
+	void create_glyph_quad(const Glyph &, PrimitiveBuilder &) const;
 	float get_glyph_advance(unsigned, unsigned = 0) const;
 };