source: trunk/third/librsvg/test-rsvg.c @ 17277

/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*-

   test-rsvg.c: Command line utility for exercising rsvg.
 
   Copyright (C) 2000 Eazel, Inc.
  
   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.
  
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.
  
   You should have received a copy of the GNU General Public
   License along with this program; if not, write to the
   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.
  
   Author: Raph Levien <raph@artofcode.com>
*/

#include <stdio.h>
#include <stdlib.h>
#include <png.h>
#include <popt.h>

#include <gdk-pixbuf/gdk-pixbuf.h>

#include "rsvg.h"


/* The following routine is lifted wholesale from nautilus-icon-factory.c.
   It should find a permanent home somewhere else, at which point it should
   be deleted here and simply linked. -RLL
*/

/* utility routine for saving a pixbuf to a png file.
 * This was adapted from Iain Holmes' code in gnome-iconedit, and probably
 * should be in a utility library, possibly in gdk-pixbuf itself.
 * 
 * It is split up into save_pixbuf_to_file and save_pixbuf_to_file_internal
 * to work around a gcc warning about handle possibly getting clobbered by
 * longjmp. Declaring handle 'volatile FILE *' didn't work as it should have.
 */
static gboolean
save_pixbuf_to_file_internal (GdkPixbuf *pixbuf, char *filename, FILE *handle)
{
        char *buffer;
        gboolean has_alpha;
        int width, height, depth, rowstride;
        guchar *pixels;
        png_structp png_ptr;
        png_infop info_ptr;
        png_text text[2];
        int i;
        
        png_ptr = png_create_write_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
        if (png_ptr == NULL) {
                return FALSE;
        }

        info_ptr = png_create_info_struct (png_ptr);
        if (info_ptr == NULL) {
                png_destroy_write_struct (&png_ptr, (png_infopp)NULL);
                return FALSE;
        }

        if (setjmp (png_ptr->jmpbuf)) {
                png_destroy_write_struct (&png_ptr, &info_ptr);
                return FALSE;
        }

        png_init_io (png_ptr, (FILE *)handle);

        has_alpha = gdk_pixbuf_get_has_alpha (pixbuf);
        width = gdk_pixbuf_get_width (pixbuf);
        height = gdk_pixbuf_get_height (pixbuf);
        depth = gdk_pixbuf_get_bits_per_sample (pixbuf);
        pixels = gdk_pixbuf_get_pixels (pixbuf);
        rowstride = gdk_pixbuf_get_rowstride (pixbuf);

        png_set_IHDR (png_ptr, info_ptr, width, height,
                        depth, PNG_COLOR_TYPE_RGB_ALPHA,
                        PNG_INTERLACE_NONE,
                        PNG_COMPRESSION_TYPE_DEFAULT,
                        PNG_FILTER_TYPE_DEFAULT);

        /* Some text to go with the png image */
        text[0].key = "Title";
        text[0].text = filename;
        text[0].compression = PNG_TEXT_COMPRESSION_NONE;
        text[1].key = "Software";
        text[1].text = "Test-Rsvg";
        text[1].compression = PNG_TEXT_COMPRESSION_NONE;
        png_set_text (png_ptr, info_ptr, text, 2);

        /* Write header data */
        png_write_info (png_ptr, info_ptr);

        /* if there is no alpha in the data, allocate buffer to expand into */
        if (has_alpha) {
                buffer = NULL;
        } else {
                buffer = g_malloc(4 * width);
        }
        
        /* pump the raster data into libpng, one scan line at a time */ 
        for (i = 0; i < height; i++) {
                if (has_alpha) {
                        png_bytep row_pointer = pixels;
                        png_write_row (png_ptr, row_pointer);
                } else {
                        /* expand RGB to RGBA using an opaque alpha value */
                        int x;
                        char *buffer_ptr = buffer;
                        char *source_ptr = pixels;
                        for (x = 0; x < width; x++) {
                                *buffer_ptr++ = *source_ptr++;
                                *buffer_ptr++ = *source_ptr++;
                                *buffer_ptr++ = *source_ptr++;
                                *buffer_ptr++ = 255;
                        }
                        png_write_row (png_ptr, (png_bytep) buffer);            
                }
                pixels += rowstride;
        }
        
        png_write_end (png_ptr, info_ptr);
        png_destroy_write_struct (&png_ptr, &info_ptr);
        
        g_free (buffer);

        return TRUE;
}

static gboolean
save_pixbuf_to_file (GdkPixbuf *pixbuf, char *filename)
{
        FILE *handle;
        gboolean result;

        g_return_val_if_fail (pixbuf != NULL, FALSE);
        g_return_val_if_fail (filename != NULL, FALSE);
        g_return_val_if_fail (filename[0] != '\0', FALSE);

        if (!strcmp (filename, "-")) {
                handle = stdout;
        } else {
                handle = fopen (filename, "wb");
        }

        if (handle == NULL) {
                return FALSE;
        }

        result = save_pixbuf_to_file_internal (pixbuf, filename, handle);
        if (!result || handle != stdout)
                fclose (handle);

        return result;
}

int
main (int argc, char **argv)
{
        FILE *f;
        char *out_fn;
        GdkPixbuf *pixbuf;
        char *zoom_str = "1.0";
        int n_iter = 1;
        poptContext optCtx;
        struct poptOption optionsTable[] = {
                { "zoom", 'z', POPT_ARG_STRING, &zoom_str, 0, NULL, "zoom factor" },
                { "num-iter", 'n', POPT_ARG_INT, &n_iter, 0, NULL, "number of iterations" },
                POPT_AUTOHELP
                { NULL, 0, 0, NULL, 0 }
        };
        char c;
        const char * const *args;
        int i;

        optCtx = poptGetContext ("test-rsvg", argc, (const char **)argv, optionsTable, 0);

        c = poptGetNextOpt (optCtx);
        args = poptGetArgs (optCtx);

        for (i = 0; i < n_iter; i++) {
                if (args == NULL || args[0] == NULL) {
                        if (n_iter > 1) {
                                fprintf (stderr, "Can't do multiple iterations on stdin\n");
                                exit (1);
                        }

                        f = stdin;
                        out_fn = "-";
                } else {
                        f = fopen(args[0], "r");
                        if (f == NULL) {
                                fprintf(stderr, "Error opening source file %s\n", argv[0]);
                                exit (1);
                        }
                        if (args[1] == NULL)
                                out_fn = "-";
                        else
                                out_fn = (char *)args[1];
                }

                pixbuf = rsvg_render_file (f, atof (zoom_str));

                if (f != stdin)
                        fclose(f);

                if (pixbuf != NULL) {
                        if (n_iter > 1)
                                gdk_pixbuf_unref (pixbuf);
                        else
                                save_pixbuf_to_file (pixbuf, out_fn);
                } else {
                        fprintf (stderr, "Error loading SVG file.\n");
                        return 1;
                }
        }

        return 0;
}