X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=example.c;h=3dab2bace2093f70bc9d1a0625418ae45c810a8d;hb=6bf209a934fc0b73a4e0dabddbb8de1e4ec5d799;hp=d6ec4a71c9a43ef92c58439ca0bda04b6e8e7a7d;hpb=311cae99852698b5473bd092ec2c2602b2c6972a;p=libsvgtiny-pixbuf.git

diff --git a/example.c b/example.c
index d6ec4a7..3dab2ba 100644
--- a/example.c
+++ b/example.c
@@ -1,6 +1,290 @@
-#include <stdio.h>
+#include <fcntl.h> /* open */
+#include <stdio.h> /* printf, fprintf */
+#include <stdlib.h> /* malloc */
+#include <sys/stat.h> /* fstat */
+#include <unistd.h> /* read */
+
+#include <cairo.h>
+#include <gdk/gdk.h>
+#include <gdk-pixbuf/gdk-pixbuf.h>
+#include <svgtiny.h>
+
+/* Convenient typedefs for libsvgtiny */
+typedef struct svgtiny_diagram diagram_t;
+
+
+/**
+ * Render an svgtiny path using cairo.
+ */
+void render_path(cairo_t *cr, struct svgtiny_shape *path) {
+  unsigned int j;
+
+  cairo_new_path(cr);
+  for (j = 0; j != path->path_length; ) {
+    switch ((int) path->path[j]) {
+    case svgtiny_PATH_MOVE:
+      cairo_move_to(cr,
+		    path->path[j + 1],
+		    path->path[j + 2]);
+      j += 3;
+      break;
+    case svgtiny_PATH_CLOSE:
+      cairo_close_path(cr);
+      j += 1;
+      break;
+    case svgtiny_PATH_LINE:
+      cairo_line_to(cr,
+		    path->path[j + 1],
+		    path->path[j + 2]);
+      j += 3;
+      break;
+    case svgtiny_PATH_BEZIER:
+      cairo_curve_to(cr,
+		     path->path[j + 1],
+		     path->path[j + 2],
+		     path->path[j + 3],
+		     path->path[j + 4],
+		     path->path[j + 5],
+		     path->path[j + 6]);
+      j += 7;
+      break;
+    default:
+      printf("error ");
+      j += 1;
+    }
+  }
+  if (path->fill != svgtiny_TRANSPARENT) {
+    cairo_set_source_rgb(cr,
+			 svgtiny_RED(path->fill) / 255.0,
+			 svgtiny_GREEN(path->fill) / 255.0,
+			 svgtiny_BLUE(path->fill) / 255.0);
+    cairo_fill_preserve(cr);
+  }
+  if (path->stroke != svgtiny_TRANSPARENT) {
+    cairo_set_source_rgb(cr,
+			 svgtiny_RED(path->stroke) / 255.0,
+			 svgtiny_GREEN(path->stroke) / 255.0,
+			 svgtiny_BLUE(path->stroke) / 255.0);
+    cairo_set_line_width(cr, path->stroke_width);
+    cairo_stroke_preserve(cr);
+  }
+}
+
+/*
+ * @brief Parse an SVG file into a diagram_t structure.
+ *
+ * @param path
+ *   The path to the SVG file.
+ *
+ * @return If successful, a pointer to a @c diagram_t structure is
+ *   returned; if not, @c NULL is returned. You are expected to @c
+ *   svgtiny_free the result if it is valid.
+ */
+diagram_t* svgtiny_diagram_from_path(char* path, int width, int height) {
+  diagram_t *diagram;
+
+  int fd;
+  size_t bytecount;
+  char *buffer;
+  size_t bytesread;
+  struct stat sb;
+  svgtiny_code code;
+
+  /* load file into memory buffer */
+  fd = open(path, O_RDONLY);
+  if (fd == -1) {
+    perror(path);
+    return NULL;
+  }
+
+  if (fstat(fd, &sb)) {
+    perror(path);
+    return NULL;
+  }
+  bytecount = sb.st_size;
+
+  buffer = malloc(bytecount);
+  if (!buffer) {
+    fprintf(stderr, "Unable to allocate %zd bytes\n", bytecount);
+    return NULL;
+  }
+
+  bytesread = read(fd, buffer, bytecount);
+  if (bytesread != bytecount) {
+    perror(path);
+    return NULL;
+  }
+  close(fd);
+
+
+  /* create svgtiny object */
+  diagram = svgtiny_create();
+  if (!diagram) {
+    fprintf(stderr, "svgtiny_create() failed\n");
+    return NULL;
+  }
+
+  code = svgtiny_parse(diagram, buffer, bytecount, path, width, height);
+  free(buffer);
+
+  if (code != svgtiny_OK) {
+    fprintf(stderr, "svgtiny_parse failed: ");
+    switch (code) {
+    case svgtiny_OUT_OF_MEMORY:
+      fprintf(stderr, "svgtiny_OUT_OF_MEMORY");
+      break;
+    case svgtiny_LIBDOM_ERROR:
+      fprintf(stderr, "svgtiny_LIBDOM_ERROR");
+      break;
+    case svgtiny_NOT_SVG:
+      fprintf(stderr, "svgtiny_NOT_SVG");
+      break;
+    case svgtiny_SVG_ERROR:
+      fprintf(stderr, "svgtiny_SVG_ERROR: line %i: %s",
+	      diagram->error_line,
+	      diagram->error_message);
+      break;
+    default:
+      fprintf(stderr, "unknown svgtiny_code %i", code);
+      break;
+    }
+    fprintf(stderr, "\n");
+    return NULL;
+  }
+
+  return diagram;
+}
+
+/*
+ * @brief Create a cairo context from a libsvgtiny diagram.
+ *
+ * @param diagram
+ *   A pointer to a valid libsvgtiny diagram.
+ *
+ * @return If successful, a pointer to a @c cairo_t context structure
+ *   is returned; if not, @c NULL is returned. You are expected to @c
+ *   cairo_destroy the result if it is valid.
+ */
+cairo_t* cairo_context_from_diagram(diagram_t* diagram) {
+  cairo_t* cr;
+  cairo_surface_t* surface;
+  cairo_status_t crs;
+  unsigned int i;
+
+  surface = cairo_image_surface_create(CAIRO_FORMAT_RGB24,
+				       diagram->width,
+				       diagram->height);
+
+  crs = cairo_surface_status(surface);
+  if (crs != CAIRO_STATUS_SUCCESS) {
+    fprintf(stderr,
+	    "cairo_image_surface_create failed: %s\n",
+	    cairo_status_to_string(crs));
+    cairo_surface_destroy(surface);
+    return NULL;
+  }
+
+  cr = cairo_create(surface);
+  crs = cairo_status(cr);
+
+  /* Immediately destroy the surface which is now accessible as
+     cr->target */
+  cairo_surface_destroy(surface);
+
+  if (crs != CAIRO_STATUS_SUCCESS) {
+    fprintf(stderr,
+	    "cairo_create failed: %s\n",
+	    cairo_status_to_string(crs));
+    cairo_destroy(cr);
+    return NULL;
+  }
+
+  cairo_set_source_rgb(cr, 1, 1, 1);
+  cairo_paint(cr);
+
+  /* Loop through the shapes in the diagram... */
+  for (i = 0; i != diagram->shape_count; i++) {
+
+    /* If this shape is a path, just render it. */
+    if (diagram->shape[i].path) {
+      render_path(cr, &diagram->shape[i]);
+    }
+
+    /* If this shape is text... */
+    if (diagram->shape[i].text) {
+      /* Figure out what color to use from the R/G/B components of the
+	 shape's stroke. */
+      cairo_set_source_rgb(cr,
+			   svgtiny_RED(diagram->shape[i].stroke) / 255.0,
+			   svgtiny_GREEN(diagram->shape[i].stroke) / 255.0,
+			   svgtiny_BLUE(diagram->shape[i].stroke) / 255.0);
+      /* Then move to the actual position of the text within the
+	 shape... */
+      cairo_move_to(cr,
+		    diagram->shape[i].text_x,
+		    diagram->shape[i].text_y);
+
+      /* and draw it. */
+      cairo_show_text(cr, diagram->shape[i].text);
+    }
+  }
+
+
+  /* Check the status again just for good measure? */
+  crs = cairo_status(cr);
+  if (crs != CAIRO_STATUS_SUCCESS) {
+    fprintf(stderr,
+	    "cairo error: %s\n",
+	    cairo_status_to_string(crs));
+    cairo_destroy(cr);
+    return NULL;
+  }
+
+  return cr;
+}
 
 int main(int argc, char** argv) {
-  printf("Hello, world!\n");
+  char* svgpath;
+  char* pngpath;
+  int pngwidth = 1024, pngheight = 1024;
+
+  diagram_t* diagram;
+  cairo_t *cr = 0;
+
+  GdkPixbuf* pb;
+
+  /* Parse arguments, and maybe print usage */
+  if (argc < 3) {
+    printf("Usage: %s INPUT OUTPUT\n", argv[0]);
+    printf("Convert an SVG file (INPUT) to a PNG file (OUTPUT)\n");
+    return 2;
+  }
+
+  svgpath = argv[1];
+  pngpath = argv[2];
+
+  diagram = svgtiny_diagram_from_path(svgpath, pngwidth, pngheight);
+  if (!diagram) {
+    return 1;
+  }
+
+  cr = cairo_context_from_diagram(diagram);
+  if (!cr) {
+    svgtiny_free(diagram);
+    return 1;
+  }
+
+  pb = gdk_pixbuf_get_from_surface(cairo_get_target(cr),
+				   0,
+				   0,
+				   pngwidth,
+				   pngheight);
+
+
+  if (pb) {
+    gdk_pixbuf_save(pb, pngpath, "png", NULL, NULL);
+    g_object_unref(pb);
+  }
+
   return 0;
 }