font.cpp

/***************************************************************************
 *   Copyright (C) 2010 by Terraneo Federico                               *
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 *   file must still be made available in accordance with the GNU General  *
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#include "font.h"
#include "misc_inst.h"
#include <cstring>

using namespace std;

namespace mxgui {

//
// Class Font
//

bool Font::isInRange(char32_t c) const
{
    for(int i=0;i<numBlocks;i+=2)
		if(c >= blocks[i] && c < blocks[i]+blocks[i+1])
			return true;
	return false;
}

unsigned int Font::getVirtualCodepoint(char32_t codepoint) const
{	
	// traverse the ranges until the right one is found
	int i=2;
	// codepoint of the character as if we had one big contiguous range
	unsigned int virtualCodepoint=0;
	while(i<2*(numBlocks-1) && blocks[i]<=codepoint)
	{
		virtualCodepoint+=blocks[i-1];
    	i+=2;
	}

	// we end up in the first range after our character,
	// so need to go back
	char32_t rangeBase=blocks[i-2];
	unsigned short rangeOffset=codepoint-rangeBase;
	if(codepoint <= (rangeBase+blocks[i-1]))
		virtualCodepoint+=rangeOffset;
	else
	    virtualCodepoint=numGlyphs-1;

	return virtualCodepoint;
}
	
short int Font::calculateLength(const char *s) const
{
    if(isFixedWidth())
    {
        return strlen(s)*width;
    } else {
        short int result=0;
		char32_t c;
		while((c=miosix::Unicode::nextUtf8(s))!='\0')
        {
			unsigned int vc = getVirtualCodepoint(c);
		    if(!isInRange(c)) result+=widths[numGlyphs-1];//Width of startchar
            else result+=widths[vc];
        }
        return result;
    }
}

void Font::generatePalette(Color out[4], Color fgcolor, Color bgcolor)
{
    #ifdef MXGUI_COLOR_DEPTH_16_BIT
    unsigned short fgR=fgcolor; //& 0xf800; Optimization, & not required
    unsigned short bgR=bgcolor; //& 0xf800; Optimization, & not required
    unsigned short fgG=fgcolor & 0x7e0;
    unsigned short bgG=bgcolor & 0x7e0;
    unsigned short fgB=fgcolor & 0x1f;
    unsigned short bgB=bgcolor & 0x1f;
    unsigned short deltaR=((fgR-bgR)/3) & 0xf800;
    unsigned short deltaG=((fgG-bgG)/3) & 0x7e0;
    unsigned short deltaB=((fgB-bgB)/3) & 0x1f;
    unsigned short delta=deltaR | deltaG | deltaB;
    out[3]=fgcolor;
    out[2]=Color(bgcolor+2*delta);
    out[1]=Color(bgcolor+delta);
    out[0]=bgcolor;
    #elif defined(MXGUI_COLOR_DEPTH_8_BIT)
    #error TODO
    #elif defined(MXGUI_COLOR_DEPTH_1_BIT_LINEAR)
    out[0]=out[1]=bgcolor ? white : black;
    out[2]=out[3]=fgcolor ? white : black;
    #else
    #error unsupported color depth
    #endif
}

}  //namespace mxgui