Function DrawChar

LibLemon/src/gfx/text.cpp:15–72

    extern Font* mainFont;

    int DrawChar(char character, int x, int y, uint8_t r, uint8_t g, uint8_t b, surface_t* surface, rect_t limits, Font* font){
        if (!isprint(character)) {
            return 0;
        }

        if(y >= surface->height || x >= surface->width || y >= limits.height || x >= limits.width) return 0;
        
        if((fontState != 1 && fontState != -1) || !font->face) InitializeFonts();
        if(fontState == -1){ //
            character &= 0x7F;

            for(int i = 0; i < 12; i++) {
                uint8_t line = font_default[i * 128 + character];

                for(int j = 0; j < 8; j++) {
                    if(line & 0x80)
                        DrawRect(j + x, i + y, 1, 1, r, g, b, surface);
                    line <<= 1; // Shift line left by one
                }
            }
            return 8;
        }

        uint32_t colour_i = 0xFF000000 | (r << 16) | (g << 8) | b;
        uint32_t* buffer = (uint32_t*)surface->buffer; 
        if(int err = FT_Load_Char(font->face, character, FT_LOAD_RENDER)) {
            printf("Freetype Error (code: %d, font: %s)\n", err, font->id);
            throw new FontException(FontException::FontRenderError, err);
            fontState = 0;
            return 0;
        }

        int maxHeight = font->lineHeight - (font->height - font->face->glyph->bitmap_top);

        if(y + maxHeight >= limits.y + limits.height){
            maxHeight = limits.y + limits.height - y;
        }

        if(y + maxHeight >= surface->height){
            maxHeight = surface->height - y;
        }
        
        for(int i = 0; i < static_cast<int>(font->face->glyph->bitmap.rows) && i < maxHeight; i++){
            if(y + i < 0) continue;

            uint32_t yOffset = (i + y + (font->height - font->face->glyph->bitmap_top)) * (surface->width);
            for(unsigned int j = 0; j < font->face->glyph->bitmap.width && static_cast<long>(j) + x < surface->width; j++){
                if(x + static_cast<long>(j) < 0) continue;
                if(font->face->glyph->bitmap.buffer[i * font->face->glyph->bitmap.width + j] == 255)
                    buffer[yOffset + (j + x)] = colour_i;
                else if(font->face->glyph->bitmap.buffer[i * font->face->glyph->bitmap.width + j] > 0){
                    double val = font->face->glyph->bitmap.buffer[i * font->face->glyph->bitmap.width + j] * 1.0 / 255;
                    buffer[yOffset + (j + x)] = AlphaBlend(buffer[yOffset + (j + x)], r, g, b, val);
                }
            }
        }
        return font->face->glyph->advance.x >> 6;
    }