#5436: Create IGLFont interface and let OpenGLModule return shared re…

…ferences to those FTGL wrappers. Declare drawString() method on the font itself.

include/igl.h

@@ -55,20 +55,43 @@ inline gl::ISharedGLContextHolder& GlobalOpenGLContext()
 
 const char* const MODULE_OPENGL("OpenGL");
 
-namespace wxutil { class GLWidget; }
-class wxGLContext;
+class IGLFont
+{
+public:
+    using Ptr = std::shared_ptr<IGLFont>;
+
+    enum class Style
+    {
+        Sans,	// free sans
+        Mono,	// free mono
+    };
+
+    virtual ~IGLFont() {}
+
+    // Returns the line spacing of this font
+    virtual float getLineHeight() const = 0;
+
+    /// \brief Renders \p string at the current raster-position of the current context.
+    virtual void drawString(const std::string& string) = 0;
+};
 
 class OpenGLBinding :
     public RegisterableModule
 {
 public:
     virtual ~OpenGLBinding() {}
 
+    // Acquires a shared reference to the font of the given style and size
+    virtual IGLFont::Ptr getFont(IGLFont::Style style, std::size_t size) = 0;
+
+    // Deprecated
     virtual int getFontHeight() = 0;
 
+    // Deprecated
     /// \brief Renders \p string at the current raster-position of the current context.
     virtual void drawString(const std::string& string) const = 0;
 
+    // Deprecated
     /// \brief Renders \p character at the current raster-position of the current context.
     virtual void drawChar(char character) const = 0;
 };

radiant/render/GLFont.cpp

@@ -9,7 +9,7 @@ namespace gl
 {
 
 GLFont::GLFont(Style style, unsigned int size) :
-	_pixelHeight(0),
+    _lineHeight(0),
 	_ftglFont(nullptr)
 {
     // Load the locally-provided TTF font file
@@ -18,14 +18,14 @@ GLFont::GLFont(Style style, unsigned int size) :
                            .getRuntimeDataPath()
                            + "ui/fonts/";
 
-	fontpath += style == FONT_SANS ? "FreeSans.ttf" : "FreeMono.ttf";
+	fontpath += style == Style::Sans ? "FreeSans.ttf" : "FreeMono.ttf";
 
 	_ftglFont = FTGL::ftglCreatePixmapFont(fontpath.c_str());
 
 	if (_ftglFont)
 	{
         FTGL::ftglSetFontFaceSize(_ftglFont, size, 0);
-		_pixelHeight = static_cast<int>(FTGL::ftglGetFontLineHeight(_ftglFont));
+        _lineHeight = FTGL::ftglGetFontLineHeight(_ftglFont);
 	}
 	else
 	{
@@ -42,4 +42,14 @@ GLFont::~GLFont()
 	}
 }
 
+float GLFont::getLineHeight() const
+{
+    return _lineHeight;
+}
+
+void GLFont::drawString(const std::string& string)
+{
+    FTGL::ftglRenderFont(_ftglFont, string.c_str(), FTGL::RENDER_ALL);
+}
+
 } // namespace

radiant/render/GLFont.h

@@ -2,39 +2,28 @@
 
 #include <memory>
 #include <FTGL/ftgl.h>
+#include "igl.h"
 
 namespace gl
 {
 
-class GLFont
+class GLFont :
+    public IGLFont
 {
 private:
-	int _pixelHeight;
-	FTGL::FTGLfont* _ftglFont;	
+	float _lineHeight;
+	FTGL::FTGLfont* _ftglFont;
 
 public:
-	enum Style
-	{
-		FONT_SANS,	// free sans
-		FONT_MONO,	// free mono
-	};
-
 	// the constructor will allocate the FTGL font
 	GLFont(Style style, unsigned int size);
 
 	// Destructor frees the FTGL object again
 	~GLFont();
 
-	FTGL::FTGLfont* getFtglFont()
-	{
-		return _ftglFont;
-	}
+    float getLineHeight() const override;
 
-	int getPixelHeight() const
-	{
-		return _pixelHeight;
-	}
+    void drawString(const std::string& string) override;
 };
-typedef std::shared_ptr<GLFont> GLFontPtr;
 
 } // namespace

radiant/render/OpenGLModule.cpp

@@ -22,7 +22,7 @@ void OpenGLModule::onGLDebugMessage(GLenum source, GLenum type, GLuint id, GLenu
 void OpenGLModule::sharedContextCreated()
 {
 	// Initialise the font before firing the extension initialised signal
-	_font.reset(new gl::GLFont(gl::GLFont::FONT_SANS, 14));
+	_font.reset(new gl::GLFont(IGLFont::Style::Sans, 14));
 
 #ifdef ENABLE_KHR_DEBUG_EXTENSION
     // Debugging
@@ -40,11 +40,17 @@ void OpenGLModule::sharedContextDestroyed()
 	_font.reset();
 }
 
+IGLFont::Ptr OpenGLModule::getFont(IGLFont::Style style, std::size_t size)
+{
+    // No caching in this first implementation
+    return std::make_shared<gl::GLFont>(style, size);
+}
+
 void OpenGLModule::drawString(const std::string& string) const
 {
     if (_font)
     {
-        FTGL::ftglRenderFont(_font->getFtglFont(), string.c_str(), FTGL::RENDER_ALL);
+        _font->drawString(string);
     }
 }
 
@@ -56,7 +62,7 @@ void OpenGLModule::drawChar(char character) const
 
 int OpenGLModule::getFontHeight() 
 {
-	return _font ? _font->getPixelHeight() : 0;
+	return _font ? _font->getLineHeight() : 0;
 }
 
 const std::string& OpenGLModule::getName() const

radiant/render/OpenGLModule.h

@@ -19,14 +19,16 @@ class OpenGLModule :
 private:
 	const std::string _unknownError;
 
-	gl::GLFontPtr _font;
+	IGLFont::Ptr _font;
 
 	sigc::connection _contextCreated;
 	sigc::connection _contextDestroyed;
 
 public:
 	OpenGLModule();
 
+    IGLFont::Ptr getFont(IGLFont::Style style, std::size_t size) override;
+
 	void drawString(const std::string& string) const override;
 	void drawChar(char character) const override;
 	int getFontHeight() override;