MatrixFont.cpp

/*
 * SmartMatrix Library - Methods for accessing bitmap fonts
 *
 * Copyright (c) 2014 Louis Beaudoin (Pixelmatix)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#include "SmartMatrix.h"

// depends on letters in font->Index table being arranged in ascending order
// save location of last lookup to speed up repeated lookups of the same letter
// TODO: use successive approximation to located index faster
int getBitmapFontLocation(unsigned char letter, const bitmap_font *font) {
    static int location = 0;

    if(location < 0)
        location = 0;

    if(font->Index[location] == letter)
        return location;

    if(font->Index[location] < letter) {
        for (; location < font->Chars; location++) {
            if (font->Index[location] == letter)
                return location;
        }
    } else {
        for (; location >= 0; location--) {
            if (font->Index[location] == letter)
                return location;
        }
    }

    return -1;
}

bool SmartMatrix::getBitmapFontPixelAtXY(unsigned char letter, unsigned char x, unsigned char y, const bitmap_font *font)
{
    int location;
    if (y >= font->Height)
        return false;

    location = getBitmapFontLocation(letter, font);

    if (location < 0)
        return false;

    if (font->Bitmap[(location * font->Height) + y] & (0x80 >> x))
        return true;
    else
        return false;
}

uint16_t SmartMatrix::getBitmapFontRowAtXY(unsigned char letter, unsigned char y, const bitmap_font *font) {
    int location;
    if (y >= font->Height)
        return 0x0000;

    location = getBitmapFontLocation(letter, font);

    if (location < 0)
        return 0x0000;

    return(font->Bitmap[(location * font->Height) + y]);
}

// order needs to match fontChoices enum
static const bitmap_font *fontArray[] = {
    &apple3x5,
    &apple5x7,
    &apple6x10,
    &apple8x13,
    &gohufont6x11,
    &gohufont6x11b,
};

const bitmap_font *SmartMatrix::fontLookup(fontChoices font) const {
    return fontArray[font];
}