1 files changed, 111 insertions, 0 deletions
diff --git a/image.c b/image.c
new file mode 100644
index 0000000..034dd62
--- /dev/null
+++ b/image.c
@@ -0,0 +1,111 @@
+#include "image.h"
+#include <gtk-3.0/gtk/gtk.h>
+
+GtkWidget* new_image()
+{
+    image = gtk_image_new();
+    return image;
+}
+
+int load_image(char *file_name, int win_width, int win_height)
+{
+    printf("loading: %s\n", file_name);
+    GError *error = NULL;
+    if (pixbuf != NULL)
+        g_object_unref(pixbuf);
+    pixbuf = gdk_pixbuf_new_from_file(file_name, &error);
+    if (error)
+        return -1;
+    pixbuf_width = gdk_pixbuf_get_width(GDK_PIXBUF(pixbuf));
+    pixbuf_height = gdk_pixbuf_get_height(GDK_PIXBUF(pixbuf));
+    aspect_ratio = (double)pixbuf_width / (double)pixbuf_height;
+    curr_zoom = 1.0;
+    fit_image(win_width, win_height);
+    return 1;
+}
+
+void update_pixbuf()
+{
+    if (curr_pixbuf != NULL)
+        g_object_unref(curr_pixbuf);
+    if (pixbuf == NULL)
+        return;
+    curr_pixbuf = gdk_pixbuf_scale_simple(GDK_PIXBUF(pixbuf), pixbuf_width,
+                                          pixbuf_height, GDK_INTERP_BILINEAR);
+    gtk_image_set_from_pixbuf(GTK_IMAGE(image), GDK_PIXBUF(curr_pixbuf));
+}
+
+void fit_image(int win_width, int win_height)
+{
+    if (pixbuf == NULL || win_width < 1 || win_height < 1)
+        return;
+    if (win_width < pixbuf_width && win_height > pixbuf_height) {
+        pixbuf_width = win_width;
+        pixbuf_height = (double)pixbuf_width / aspect_ratio;
+    } else if (win_width > pixbuf_width && win_height < pixbuf_height) {
+        pixbuf_height = win_height;
+        pixbuf_width = (double)pixbuf_height * aspect_ratio;
+    } else if (win_width < pixbuf_width && win_height < pixbuf_height) {
+        if (((double)win_width / (double)win_height) > aspect_ratio) {
+            pixbuf_height = win_height;
+            pixbuf_width = ((double)pixbuf_height * aspect_ratio);
+        } else {
+            pixbuf_width = win_width;
+            pixbuf_height = (double)pixbuf_width / aspect_ratio;
+        }
+    } else {
+        pixbuf_width = pixbuf_width;
+        pixbuf_height = pixbuf_height;
+    }
+
+    curr_zoom = (double)pixbuf_width / (double)pixbuf_width;
+    if (pixbuf_width < 1 || pixbuf_height < 1)
+        return;
+
+    update_pixbuf();
+}
+
+void zoom(int type)
+{
+    if (pixbuf == NULL)
+        return;
+    if (type == 0) {
+        if (curr_zoom == 1.0)
+            return;
+        curr_zoom = (double)1.0;
+    } else if (type < 0) {
+        if (curr_zoom < 0.2)
+            return;
+        curr_zoom -= (double)ZOOM_FACTOR;
+    } else if (type > 0) {
+        if (curr_zoom > 2)
+            return;
+        curr_zoom += (double)ZOOM_FACTOR;
+    }
+    pixbuf_width *= curr_zoom;
+    pixbuf_height += curr_zoom;
+
+    update_pixbuf();
+}
+
+void print_supported_formats()
+{
+    GSList *list, *it;
+    GdkPixbufFormat *format;
+    gchar **extensions;
+    gchar *ex;
+
+    list = gdk_pixbuf_get_formats();
+    if (list != NULL) {
+        for (it = list; it->next != NULL; it = it->next) {
+            format = (GdkPixbufFormat *)it->data;
+            printf("%s:", gdk_pixbuf_format_get_description(format));
+            extensions = gdk_pixbuf_format_get_extensions(format);
+            for (ex = *extensions; *ex; ex++) {
+                printf(" %s", ex);
+            }
+            printf("\n");
+        }
+        g_slist_free(list);
+    }
+}