kmx git

#include	"FTGLTextureFont.h"
#include	"FTTextureGlyph.h"
#ifdef FTGL_DEBUG
	#include "mmgr.h"
#endif


using namespace std; // for memset


inline GLuint NextPowerOf2( GLuint in)
{
     in -= 1;

     in |= in >> 16;
     in |= in >> 8;
     in |= in >> 4;
     in |= in >> 2;
     in |= in >> 1;

     return in + 1;
}


FTGLTextureFont::FTGLTextureFont()
:	maxTextSize(0),
	textureWidth(0),
	textureHeight(0),
	numTextures(0),
	textMem(0),
	glyphHeight(0),
	glyphWidth(0),
	padding(1),
	remGlyphs(0),
	xOffset(0),
	yOffset(0)
{}


FTGLTextureFont::~FTGLTextureFont()
{
	glDeleteTextures( numTextures, (const GLuint*)glTextureID);
}


FTGlyph* FTGLTextureFont::MakeGlyph( unsigned int g)
{
	FT_Glyph* ftGlyph = face.Glyph( g, FT_LOAD_NO_HINTING);
	
	if( ftGlyph)
	{
		// Estimate the glyph size size - global bbox
		glyphHeight = ( charSize.Height());
		glyphWidth = ( charSize.Width());
		
		// Is there a current texture
		if( numTextures == 0)
		{
			glTextureID[0] = CreateTexture();
			xOffset = yOffset = padding;
			++numTextures;
		}
		
		// will it fit in the current texture
		if( xOffset > ( textureWidth - glyphWidth))
		{
			xOffset = padding;
			yOffset += glyphHeight;
			
			if( yOffset > ( textureHeight - glyphHeight))
			{
				// no - make a new texture
				glTextureID[numTextures] = CreateTexture();
				yOffset = padding;
				++numTextures;
			}
		}
		
		// yes - load the glyph
		FTTextureGlyph* tempGlyph = new FTTextureGlyph( *ftGlyph, glTextureID[numTextures - 1],
															xOffset, yOffset, textureWidth, textureHeight);
		
		xOffset += tempGlyph->BBox().x2 - tempGlyph->BBox().x1 + padding;
		
		--remGlyphs;
		return tempGlyph;
	}
	
	err = face.Error();
	return NULL;

}


bool FTGLTextureFont::MakeGlyphList()
{
	if( !maxTextSize)
		glGetIntegerv( GL_MAX_TEXTURE_SIZE, (GLint*)&maxTextSize);

	remGlyphs = numGlyphs;

	FTFont::MakeGlyphList();
	
	return !err; // FIXME what err?
}


void FTGLTextureFont::GetSize()
{
	//work out the max width. Most likely maxTextSize
	textureWidth = NextPowerOf2( (remGlyphs * glyphWidth) + padding * 2);
	if( textureWidth > maxTextSize)
	{
		textureWidth = maxTextSize;
	}
	
	int h = static_cast<int>( (textureWidth - padding * 2) / glyphWidth);
        
	textureHeight = NextPowerOf2( (( numGlyphs / h) + 1) * glyphHeight);
	textureHeight = textureHeight > maxTextSize ? maxTextSize : textureHeight;
}


int FTGLTextureFont::CreateTexture()
{	
	// calc the size
	GetSize();
	
	// allocate some mem and clear it to black
	int totalMem = textureWidth * textureHeight;
	textMem = new unsigned char[totalMem]; // GL_ALPHA texture;
	memset( textMem, 0, totalMem);

	// Create the blank texture
	int textID;
	glGenTextures( 1, (GLuint*)&textID);

	glPixelStorei( GL_UNPACK_ALIGNMENT, 1); //What does this do exactly?
	glBindTexture( GL_TEXTURE_2D, textID);
	glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
	glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
	glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
	glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

	glTexImage2D( GL_TEXTURE_2D, 0, GL_ALPHA, textureWidth, textureHeight, 0, GL_ALPHA, GL_UNSIGNED_BYTE, textMem);

	delete [] textMem;

	return textID;
}


void FTGLTextureFont::render( const char* string)
{	
	glPushAttrib( GL_ENABLE_BIT | GL_HINT_BIT | GL_LINE_BIT | GL_PIXEL_MODE_BIT);
	
	glEnable(GL_BLEND);
 	glBlendFunc( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); // GL_ONE
 	
 	FTFont::render( string);

	glPopAttrib();
}


void FTGLTextureFont::render( const wchar_t* string)
{	
	glPushAttrib( GL_ENABLE_BIT | GL_HINT_BIT | GL_LINE_BIT | GL_PIXEL_MODE_BIT);
	
	glEnable(GL_BLEND);
 	glBlendFunc( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); // GL_ONE
 	
 	FTFont::render( string);
	
	glPopAttrib();
}
kc3-lang/ftgl/src/FTGLTextureFont.cpp

Commit

src/FTGLTextureFont.cpp
