/*
 * TFT2TGA    Copyright 2004 John Maushammer
 *
 * translates 280x240 image suitable for an LCD display into a .TGA format.
 * Both files are uncompressed. Quick & dirty - could be improved.
 *
 * http://www.maushammer.com/systems/dakotadigital/lcd.html
 */
 
#include <stdio.h>

main(int argc, char * argv[])
{
    FILE *fin, *fout;
    char filein[200], fileout[200];
    int x,y,phase;
    unsigned char inbyte;
    unsigned char red, green, blue;
    unsigned char header[20]= {0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x18, 0x01, 0xdc, 0x00, 0x18, 0x20, 0x00, 0x00};
    unsigned char trailer[26]= {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
       0x00, 0x00, 0x54, 0x52, 0x55, 0x45, 0x56, 0x49, 0x53, 0x49, 0x4f, 0x4e,
       0x2d, 0x58, 0x46, 0x49, 0x4c, 0x45, 0x2e, 0x00};  
    
    if(argc!=2) {
        printf("Usage: tft2tga filebasename\n\n");
        exit(1);
    }
    sprintf(filein, "%s.TFT", argv[1]);
    sprintf(fileout, "%s.TGA", argv[1]);
    if(NULL==(fin=fopen(filein, "rb"))) {
        printf("unable to open input file '%s' for reading\n\n", filein);
        exit(1);
    }    
    if(NULL==(fout=fopen(fileout, "wb"))) {
        printf("unable to open output file '%s' for writing\n\n", fileout);
        fclose(fin);
        exit(1);
    }    
    
    /* write tga header */
    for(x=0; x<20; x++) {
       fputc(header[x], fout);
    }
      
      
    /* File format is 280x220). Even lines RGB, odd lines GBR */
    for(y=0; y<220; y++) {
        red = 0; green = 0; blue = 0;
        for(x=0; x<280; x++) {
           inbyte = fgetc(fin) * 4;  /* 6 bit -> 8 bit scaling conversion */
           phase=(x + (y & 1)) % 3;
#if 0 /* draw with lcd artifacts: */
           switch(phase) {
             case 0: 
               fputc(inbyte, fout); fputc(0, fout); fputc(0, fout); break;  /* Red */
             case 1: 
               fputc(0, fout); fputc(inbyte, fout); fputc(0, fout); break;  /* Blue */
             case 2: 
               fputc(0, fout); fputc(0, fout); fputc(inbyte, fout); break;  /* Green */
           }    
#else /* attempt better picture (could still be improved, this alg. will bleed) */
           switch(phase) {
             case 0: 
               red = inbyte; break;
             case 1: 
               blue = inbyte; break;
             case 2: 
               green = inbyte; break;
           }    
           fputc(red, fout); fputc(blue, fout); fputc(green, fout);
#endif
        }
    }
        
    /* write tga trailer */
    for(x=0; x<24; x++) {
       fputc(trailer[x], fout);
    }
 
    fclose(fin);
    fclose(fout);
}