testdmabuf: Test dmabuf viewports

Allow specifying padding via --padding. The argument to --padding
is a string of up to 4 comma-separated numbers, for the left, right,
top, bottom padding. If less numbers are given, the remaining ones
are set to zero.

This commit also includes an image that can be used for testing with

testdmabuf --padding 20,20,20,20 NV12 padded.png

tests/gtkclipper.c

@@ -0,0 +1,157 @@
+#include "gtk/gtk.h"
+#include "gtkclipperprivate.h"
+
+struct _GtkClipper
+{
+  GObject parent_instance;
+
+  GdkPaintable *paintable;
+  graphene_rect_t clip;
+};
+
+struct _GtkClipperClass
+{
+  GObjectClass parent_class;
+};
+
+static void
+gtk_clipper_paintable_snapshot (GdkPaintable *paintable,
+                                GdkSnapshot  *snapshot,
+                                double        width,
+                                double        height)
+{
+  GtkClipper *self = GTK_CLIPPER (paintable);
+  float sx, sy;
+
+  gtk_snapshot_save (snapshot);
+
+  sx = gdk_paintable_get_intrinsic_width (self->paintable) / self->clip.size.width;
+  sy = gdk_paintable_get_intrinsic_height (self->paintable) / self->clip.size.height;
+
+  gtk_snapshot_push_clip (snapshot, &GRAPHENE_RECT_INIT (0, 0, width, height));
+
+  gtk_snapshot_translate (snapshot, &GRAPHENE_POINT_INIT (- self->clip.origin.x * width / self->clip.size.width,
+                                                          - self->clip.origin.y * height / self->clip.size.height));
+  gdk_paintable_snapshot (self->paintable, snapshot, width * sx, height * sy);
+  gtk_snapshot_pop (snapshot);
+  gtk_snapshot_restore (snapshot);
+}
+
+static GdkPaintable *
+gtk_clipper_paintable_get_current_image (GdkPaintable *paintable)
+{
+  GtkClipper *self = GTK_CLIPPER (paintable);
+  GdkPaintable *current_paintable, *current_self;
+
+  current_paintable = gdk_paintable_get_current_image (self->paintable);
+  current_self = gtk_clipper_new (current_paintable, &self->clip);
+  g_object_unref (current_paintable);
+
+  return current_self;
+}
+
+static GdkPaintableFlags
+gtk_clipper_paintable_get_flags (GdkPaintable *paintable)
+{
+  GtkClipper *self = GTK_CLIPPER (paintable);
+
+  return gdk_paintable_get_flags (self->paintable);
+}
+
+static int
+gtk_clipper_paintable_get_intrinsic_width (GdkPaintable *paintable)
+{
+  GtkClipper *self = GTK_CLIPPER (paintable);
+
+  return self->clip.size.width;
+}
+
+static int
+gtk_clipper_paintable_get_intrinsic_height (GdkPaintable *paintable)
+{
+  GtkClipper *self = GTK_CLIPPER (paintable);
+
+  return self->clip.size.height;
+}
+
+static double gtk_clipper_paintable_get_intrinsic_aspect_ratio (GdkPaintable *paintable)
+{
+  GtkClipper *self = GTK_CLIPPER (paintable);
+
+  return self->clip.size.width / (double) self->clip.size.height;
+};
+
+static void
+gtk_clipper_paintable_init (GdkPaintableInterface *iface)
+{
+  iface->snapshot = gtk_clipper_paintable_snapshot;
+  iface->get_current_image = gtk_clipper_paintable_get_current_image;
+  iface->get_flags = gtk_clipper_paintable_get_flags;
+  iface->get_intrinsic_width = gtk_clipper_paintable_get_intrinsic_width;
+  iface->get_intrinsic_height = gtk_clipper_paintable_get_intrinsic_height;
+  iface->get_intrinsic_aspect_ratio = gtk_clipper_paintable_get_intrinsic_aspect_ratio;
+}
+
+G_DEFINE_TYPE_EXTENDED (GtkClipper, gtk_clipper, G_TYPE_OBJECT, 0,
+                        G_IMPLEMENT_INTERFACE (GDK_TYPE_PAINTABLE,
+                                               gtk_clipper_paintable_init))
+
+static void
+gtk_clipper_dispose (GObject *object)
+{
+  GtkClipper *self = GTK_CLIPPER (object);
+
+  if (self->paintable)
+    {
+      const guint flags = gdk_paintable_get_flags (self->paintable);
+
+      if ((flags & GDK_PAINTABLE_STATIC_CONTENTS) == 0)
+        g_signal_handlers_disconnect_by_func (self->paintable, gdk_paintable_invalidate_contents, self);
+
+      if ((flags & GDK_PAINTABLE_STATIC_SIZE) == 0)
+        g_signal_handlers_disconnect_by_func (self->paintable, gdk_paintable_invalidate_size, self);
+
+      g_clear_object (&self->paintable);
+    }
+
+  G_OBJECT_CLASS (gtk_clipper_parent_class)->dispose (object);
+}
+
+static void
+gtk_clipper_class_init (GtkClipperClass *klass)
+{
+  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+
+  gobject_class->dispose = gtk_clipper_dispose;
+}
+
+static void
+gtk_clipper_init (GtkClipper *self)
+{
+}
+
+GdkPaintable *
+gtk_clipper_new (GdkPaintable          *paintable,
+                 const graphene_rect_t *clip)
+{
+  GtkClipper *self;
+  guint flags;
+
+  g_return_val_if_fail (GDK_IS_PAINTABLE (paintable), NULL);
+  g_return_val_if_fail (clip != NULL, NULL);
+
+  self = g_object_new (GTK_TYPE_CLIPPER, NULL);
+
+  self->paintable = g_object_ref (paintable);
+  flags = gdk_paintable_get_flags (paintable);
+
+  if ((flags & GDK_PAINTABLE_STATIC_CONTENTS) == 0)
+    g_signal_connect_swapped (paintable, "invalidate-contents", G_CALLBACK (gdk_paintable_invalidate_contents), self);
+
+  if ((flags & GDK_PAINTABLE_STATIC_SIZE) == 0)
+    g_signal_connect_swapped (paintable, "invalidate-size", G_CALLBACK (gdk_paintable_invalidate_size), self);
+
+  self->clip = *clip;
+
+  return GDK_PAINTABLE (self);
+}

tests/gtkclipperprivate.h

@@ -0,0 +1,16 @@
+#pragma once
+
+#include <gdk/gdk.h>
+#include <graphene.h>
+
+G_BEGIN_DECLS
+
+#define GTK_TYPE_CLIPPER (gtk_clipper_get_type ())
+
+G_DECLARE_FINAL_TYPE (GtkClipper, gtk_clipper, GTK, CLIPPER, GObject)
+
+GdkPaintable * gtk_clipper_new (GdkPaintable          *paintable,
+                                const graphene_rect_t *clip);
+
+G_END_DECLS
+

tests/meson.build

@@ -133,7 +133,7 @@ endif
 
 if os_linux
   gtk_tests += [
-    ['testdmabuf'],
+    ['testdmabuf', ['testdmabuf.c', 'gtkclipper.c']],
   ]
 endif
 

tests/testdmabuf.c

@@ -9,6 +9,9 @@
 #ifdef GDK_RENDERING_VULKAN
 #include <vulkan/vulkan.h>
 #endif
+
+#include "gtkclipperprivate.h"
+
 /* For this to work, you may need to give /dev/dma_heap/system
  * lax permissions.
  */
@@ -449,13 +452,12 @@ texture_builder_set_planes (GdkDmabufTextureBuilder *builder,
 }
 
 static GdkTexture *
-make_dmabuf_texture (const char *filename,
+make_dmabuf_texture (GdkTexture *texture,
                      guint32     format,
                      gboolean    disjoint,
                      gboolean    premultiplied,
                      gboolean    flip)
 {
-  GdkTexture *texture;
   GdkTextureDownloader *downloader;
   int width, height;
   gsize rgb_stride, rgb_size;
@@ -471,8 +473,6 @@ make_dmabuf_texture (const char *filename,
   else
     g_print ("Using memfd\n");
 
-  texture = gdk_texture_new_from_filename (filename, NULL);
-
   width = gdk_texture_get_width (texture);
   height = gdk_texture_get_height (texture);
   rgb_stride = 4 * width;
@@ -490,8 +490,6 @@ make_dmabuf_texture (const char *filename,
   gdk_texture_downloader_download_into (downloader, rgb_data, rgb_stride);
   gdk_texture_downloader_free (downloader);
 
-  g_object_unref (texture);
-
   if (flip)
     {
       for (int y = 0; y < height; y++)
@@ -643,7 +641,7 @@ static void
 usage (void)
 {
   char *formats = supported_formats_to_string ();
-  g_print ("Usage: testdmabuf [--undecorated][--disjoint][--download-to FILE] FORMAT FILE\n"
+  g_print ("Usage: testdmabuf [--undecorated][--disjoint][--download-to FILE][--padding PADDING] FORMAT FILE\n"
            "Supported formats: %s\n", formats);
   g_free (formats);
   exit (1);
@@ -717,6 +715,9 @@ toggle_flip (GtkWidget *widget,
 {
   GtkPicture *picture = data;
 
+  if (!texture_flipped)
+    return FALSE;
+
   if (gtk_picture_get_paintable (picture) == GDK_PAINTABLE (texture))
     gtk_picture_set_paintable (picture, GDK_PAINTABLE (texture_flipped));
   else
@@ -756,6 +757,10 @@ main (int argc, char *argv[])
   GtkShortcutTrigger *trigger;
   GtkShortcutAction *action;
   GtkShortcut *shortcut;
+  GdkPaintable *paintable;
+  GdkTexture *orig;
+  int padding[4] = { 0, }; /* left, right, top, bottom */
+  int padding_set = 0;
 
   for (i = 1; i < argc; i++)
     {
@@ -775,6 +780,37 @@ main (int argc, char *argv[])
 
           save_filename = argv[i];
         }
+      else if (g_str_equal (argv[i], "--padding"))
+        {
+          if (padding_set < 4)
+            {
+              char **strv;
+
+              i++;
+              if (i == argc)
+                usage ();
+
+              strv = g_strsplit (argv[i], ",", 0);
+              if (g_strv_length (strv) > 4)
+                g_error ("Too much padding");
+
+              for (padding_set = 0; padding_set < 4; padding_set++)
+                {
+                  guint64 num;
+                  GError *error = NULL;
+
+                  if (!strv[padding_set])
+                    break;
+
+                  if (!g_ascii_string_to_unsigned (strv[padding_set], 10, 0, 100, &num, &error))
+                    g_error ("%s", error->message);
+
+                  padding[padding_set] = (int) num;
+               }
+            }
+          else
+            g_error ("Too much padding");
+        }
       else
         break;
     }
@@ -793,8 +829,21 @@ main (int argc, char *argv[])
   /* Get the list of supported formats with GDK_DEBUG=opengl */
   gdk_display_get_dmabuf_formats (gdk_display_get_default ());
 
-  texture = make_dmabuf_texture (filename, format, disjoint, premultiplied, FALSE);
-  texture_flipped = make_dmabuf_texture (filename, format, disjoint, premultiplied, TRUE);
+  orig = gdk_texture_new_from_filename (filename, NULL);
+  texture = make_dmabuf_texture (orig, format, disjoint, premultiplied, FALSE);
+  texture_flipped = make_dmabuf_texture (orig, format, disjoint, premultiplied, TRUE);
+  g_object_unref (orig);
+
+  if (padding_set > 0)
+    {
+      paintable = gtk_clipper_new (GDK_PAINTABLE (texture),
+                                   &GRAPHENE_RECT_INIT (padding[0],
+                                                        padding[2],
+                                                        gdk_texture_get_width (texture) - padding[0] - padding[1],
+                                                        gdk_texture_get_height (texture) - padding[2] - padding[3]));
+    }
+  else
+    paintable = GDK_PAINTABLE (texture);
 
   if (save_filename)
     gdk_texture_save_to_png (texture, save_filename);
@@ -804,7 +853,7 @@ main (int argc, char *argv[])
   if (fullscreen)
     gtk_window_fullscreen (GTK_WINDOW (window));
 
-  picture = gtk_picture_new_for_paintable (GDK_PAINTABLE (texture));
+  picture = gtk_picture_new_for_paintable (paintable);
   offload = gtk_graphics_offload_new (picture);
   gtk_widget_set_halign (offload, GTK_ALIGN_CENTER);
   gtk_widget_set_valign (offload, GTK_ALIGN_CENTER);