mutter/clutter/win32/clutter-backend-win32.c
Robert Bragg b499696d83 Use paint volumes to do automatic culling
This uses actor paint volumes to perform culling during
clutter_actor_paint.

When performing a clipped redraw (because only a few localized actors
changed) then as we traverse the scenegraph painting the actors we can
now ignore actors that don't intersect the clip region. Early testing
shows this can have a big performance benefit; e.g. 100% fps improvement
for test-state with culling enabled and we hope that there are even much
more compelling examples than that in the real world,

Most Clutter applications are 2Dish interfaces and have quite a lot of
actors that get continuously painted when anything is animated. The
dynamic actors are often localized to an area of user focus though so
with culling we can completely avoid painting any of the static actors
outside the current clip region.

Obviously the cost of culling has to be offset against the cost of
painting to determine if it's a win, but our (limited) testing suggests
it should be a win for most applications.

Note: we hope we will be able to also bring another performance bump
from culling with another iteration - hopefully in the 1.6 cycle - to
avoid doing the culling in screen space and instead do it in the stage's
model space. This will hopefully let us minimize the cost of
transforming the actor volumes for culling.
2010-09-29 15:12:58 +01:00

599 lines
17 KiB
C

/* Clutter.
* An OpenGL based 'interactive canvas' library.
* Authored By Matthew Allum <mallum@openedhand.com>
* Copyright (C) 2006-2007 OpenedHand
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <windows.h>
#include "clutter-backend-win32.h"
#include "clutter-stage-win32.h"
#include "clutter-win32.h"
#include "clutter-device-manager-win32.h"
#include "../clutter-event.h"
#include "../clutter-main.h"
#include "../clutter-input-device.h"
#include "../clutter-debug.h"
#include "../clutter-private.h"
#include "../clutter-version.h"
#include "cogl/cogl.h"
G_DEFINE_TYPE (ClutterBackendWin32, clutter_backend_win32,
CLUTTER_TYPE_BACKEND);
typedef int (WINAPI * SwapIntervalProc) (int interval);
/* singleton object */
static ClutterBackendWin32 *backend_singleton = NULL;
static gchar *clutter_vblank_name = NULL;
static HINSTANCE clutter_hinst = NULL;
gboolean
clutter_backend_win32_pre_parse (ClutterBackend *backend,
GError **error)
{
const gchar *env_string;
if ((env_string = g_getenv ("CLUTTER_VBLANK")))
clutter_vblank_name = g_strdup (env_string);
return TRUE;
}
static void
clutter_backend_win32_init_events (ClutterBackend *backend)
{
ClutterBackendWin32 *backend_win32 = CLUTTER_BACKEND_WIN32 (backend);
CLUTTER_NOTE (EVENT, "initialising the event loop");
backend_win32->device_manager =
g_object_new (CLUTTER_TYPE_DEVICE_MANAGER_WIN32,
"backend", backend_win32,
NULL);
_clutter_backend_win32_events_init (backend);
}
HCURSOR
_clutter_backend_win32_get_invisible_cursor (ClutterBackend *backend)
{
ClutterBackendWin32 *backend_win32 = CLUTTER_BACKEND_WIN32 (backend);
if (backend_win32->invisible_cursor == NULL)
backend_win32->invisible_cursor =
LoadCursor (clutter_hinst, MAKEINTRESOURCE (42));
return backend_win32->invisible_cursor;
}
static const GOptionEntry entries[] =
{
{
"vblank", 0,
0,
G_OPTION_ARG_STRING, &clutter_vblank_name,
"VBlank method to be used (none, default or wgl)", "METHOD"
},
{ NULL }
};
void
clutter_backend_win32_add_options (ClutterBackend *backend,
GOptionGroup *group)
{
g_option_group_add_entries (group, entries);
}
static void
clutter_backend_win32_finalize (GObject *gobject)
{
backend_singleton = NULL;
timeEndPeriod (1);
G_OBJECT_CLASS (clutter_backend_win32_parent_class)->finalize (gobject);
}
static void
clutter_backend_win32_dispose (GObject *gobject)
{
ClutterBackendWin32 *backend_win32 = CLUTTER_BACKEND_WIN32 (gobject);
ClutterStageManager *stage_manager;
CLUTTER_NOTE (BACKEND, "Disposing the of stages");
stage_manager = clutter_stage_manager_get_default ();
/* Destroy all of the stages. g_slist_foreach is used because the
finalizer for the stages will remove the stage from the
stage_manager's list and g_slist_foreach has some basic
protection against this */
g_slist_foreach (stage_manager->stages, (GFunc) clutter_actor_destroy, NULL);
CLUTTER_NOTE (BACKEND, "Removing the event source");
_clutter_backend_win32_events_uninit (CLUTTER_BACKEND (backend_win32));
/* Unrealize all shaders, since the GL context is going away */
_clutter_shader_release_all ();
if (backend_win32->gl_context)
{
wglMakeCurrent (NULL, NULL);
wglDeleteContext (backend_win32->gl_context);
backend_win32->gl_context = NULL;
}
if (backend_win32->dummy_dc)
{
ReleaseDC (backend_win32->dummy_hwnd, backend_win32->dummy_dc);
backend_win32->dummy_dc = NULL;
}
if (backend_win32->dummy_hwnd)
{
DestroyWindow (backend_win32->dummy_hwnd);
backend_win32->dummy_hwnd = NULL;
}
G_OBJECT_CLASS (clutter_backend_win32_parent_class)->dispose (gobject);
}
static GObject *
clutter_backend_win32_constructor (GType gtype,
guint n_params,
GObjectConstructParam *params)
{
GObjectClass *parent_class;
GObject *retval;
if (!backend_singleton)
{
parent_class = G_OBJECT_CLASS (clutter_backend_win32_parent_class);
retval = parent_class->constructor (gtype, n_params, params);
backend_singleton = CLUTTER_BACKEND_WIN32 (retval);
return retval;
}
g_warning ("Attempting to create a new backend object. This should "
"never happen, so we return the singleton instance.");
return g_object_ref (backend_singleton);
}
static gboolean
check_vblank_env (const char *name)
{
return clutter_vblank_name && !g_ascii_strcasecmp (clutter_vblank_name, name);
}
ClutterFeatureFlags
clutter_backend_win32_get_features (ClutterBackend *backend)
{
ClutterFeatureFlags flags;
const gchar *extensions;
SwapIntervalProc swap_interval;
ClutterBackendWin32 *backend_win32;
/* this will make sure that the GL context exists and is bound to a
drawable */
backend_win32 = CLUTTER_BACKEND_WIN32 (backend);
g_return_val_if_fail (backend_win32->gl_context != NULL, 0);
g_return_val_if_fail (wglGetCurrentDC () != NULL, 0);
extensions = (const gchar *) glGetString (GL_EXTENSIONS);
CLUTTER_NOTE (BACKEND,
"Checking features\n"
" GL_VENDOR: %s\n"
" GL_RENDERER: %s\n"
" GL_VERSION: %s\n"
" GL_EXTENSIONS: %s\n",
glGetString (GL_VENDOR),
glGetString (GL_RENDERER),
glGetString (GL_VERSION),
extensions);
flags = CLUTTER_FEATURE_STAGE_USER_RESIZE
| CLUTTER_FEATURE_STAGE_CURSOR
| CLUTTER_FEATURE_STAGE_MULTIPLE;
/* If the VBlank should be left at the default or it has been
disabled elsewhere (eg NVIDIA) then don't bother trying to check
for the swap control extension */
if (getenv ("__GL_SYNC_TO_VBLANK") || check_vblank_env ("default"))
CLUTTER_NOTE (BACKEND, "vblank sync: left at default at user request");
else if (_cogl_check_extension ("WGL_EXT_swap_control", extensions)
&& (swap_interval = (SwapIntervalProc)
cogl_get_proc_address ("wglSwapIntervalEXT")))
{
/* According to the specification for the WGL_EXT_swap_control
extension the default swap interval is 1 anyway, so if no
vblank is requested then we should explicitly set it to
zero */
if (check_vblank_env ("none"))
{
if (swap_interval (0))
CLUTTER_NOTE (BACKEND, "vblank sync: successfully disabled");
else
CLUTTER_NOTE (BACKEND, "vblank sync: disabling failed");
}
else
{
if (swap_interval (1))
{
flags |= CLUTTER_FEATURE_SYNC_TO_VBLANK;
CLUTTER_NOTE (BACKEND, "vblank sync: wglSwapIntervalEXT "
"vblank setup success");
}
else
CLUTTER_NOTE (BACKEND, "vblank sync: wglSwapIntervalEXT "
"vblank setup failed");
}
}
else
CLUTTER_NOTE (BACKEND, "no use-able vblank mechanism found");
CLUTTER_NOTE (BACKEND, "backend features checked");
return flags;
}
static ATOM
clutter_backend_win32_get_dummy_window_class ()
{
static ATOM klass = 0;
if (klass == 0)
{
WNDCLASSW wndclass;
memset (&wndclass, 0, sizeof (wndclass));
wndclass.lpfnWndProc = DefWindowProc;
wndclass.hInstance = GetModuleHandleW (NULL);
wndclass.lpszClassName = L"ClutterBackendWin32DummyWindow";
klass = RegisterClassW (&wndclass);
}
return klass;
}
static gboolean
clutter_backend_win32_pixel_format_is_better (const PIXELFORMATDESCRIPTOR *pfa,
const PIXELFORMATDESCRIPTOR *pfb)
{
/* Always prefer a format with a stencil buffer */
if (pfa->cStencilBits == 0)
{
if (pfb->cStencilBits > 0)
return TRUE;
}
else if (pfb->cStencilBits == 0)
return FALSE;
/* Prefer a bigger color buffer */
if (pfb->cColorBits > pfa->cColorBits)
return TRUE;
else if (pfb->cColorBits < pfa->cColorBits)
return FALSE;
/* Prefer a bigger depth buffer */
return pfb->cDepthBits > pfa->cDepthBits;
}
static int
clutter_backend_win32_choose_pixel_format (HDC dc, PIXELFORMATDESCRIPTOR *pfd)
{
int i, num_formats, best_pf = 0;
PIXELFORMATDESCRIPTOR best_pfd;
num_formats = DescribePixelFormat (dc, 0, sizeof (best_pfd), NULL);
for (i = 1; i <= num_formats; i++)
{
memset (pfd, 0, sizeof (*pfd));
if (DescribePixelFormat (dc, i, sizeof (best_pfd), pfd)
/* Check whether this format is useable by Clutter */
&& ((pfd->dwFlags & (PFD_SUPPORT_OPENGL
| PFD_DRAW_TO_WINDOW
| PFD_DOUBLEBUFFER
| PFD_GENERIC_FORMAT))
== (PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER | PFD_DRAW_TO_WINDOW))
&& pfd->iPixelType == PFD_TYPE_RGBA
&& pfd->cColorBits >= 16 && pfd->cColorBits <= 32
&& pfd->cDepthBits >= 16 && pfd->cDepthBits <= 32
/* Check whether this is a better format than one we've
already found */
&& (best_pf == 0
|| clutter_backend_win32_pixel_format_is_better (&best_pfd, pfd)))
{
best_pf = i;
best_pfd = *pfd;
}
}
*pfd = best_pfd;
return best_pf;
}
static gboolean
clutter_backend_win32_create_context (ClutterBackend *backend,
GError **error)
{
ClutterBackendWin32 *backend_win32 = CLUTTER_BACKEND_WIN32 (backend);
/* COGL assumes that there is always a GL context selected; in order
* to make sure that a WGL context exists and is made current, we
* use a small dummy window that never gets shown to which we can
* always fall back if no stage is available
*/
if (backend_win32->dummy_hwnd == NULL)
{
ATOM window_class = clutter_backend_win32_get_dummy_window_class ();
if (window_class == 0)
{
g_critical ("Unable to register window class");
return FALSE;
}
backend_win32->dummy_hwnd =
CreateWindowW ((LPWSTR) MAKEINTATOM (window_class),
L".",
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT,
CW_USEDEFAULT,
1, 1,
NULL, NULL,
GetModuleHandle (NULL),
NULL);
if (backend_win32->dummy_hwnd == NULL)
{
g_critical ("Unable to create dummy window");
return FALSE;
}
}
if (backend_win32->dummy_dc == NULL)
{
PIXELFORMATDESCRIPTOR pfd;
int pf;
backend_win32->dummy_dc = GetDC (backend_win32->dummy_hwnd);
pf = clutter_backend_win32_choose_pixel_format (backend_win32->dummy_dc,
&pfd);
if (pf == 0 || !SetPixelFormat (backend_win32->dummy_dc, pf, &pfd))
{
g_critical ("Unable to find suitable GL pixel format");
ReleaseDC (backend_win32->dummy_hwnd, backend_win32->dummy_dc);
backend_win32->dummy_dc = NULL;
return FALSE;
}
}
if (backend_win32->gl_context == NULL)
{
backend_win32->gl_context = wglCreateContext (backend_win32->dummy_dc);
if (backend_win32->gl_context == NULL)
{
g_critical ("Unable to create suitable GL context");
return FALSE;
}
}
CLUTTER_NOTE (BACKEND, "Selecting dummy 0x%x for the WGL context",
(unsigned int) backend_win32->dummy_hwnd);
wglMakeCurrent (backend_win32->dummy_dc, backend_win32->gl_context);
return TRUE;
}
static void
clutter_backend_win32_ensure_context (ClutterBackend *backend,
ClutterStage *stage)
{
ClutterStageWindow *impl;
if (stage == NULL ||
CLUTTER_ACTOR_IN_DESTRUCTION (stage) ||
((impl = _clutter_stage_get_window (stage)) == NULL))
{
CLUTTER_NOTE (MULTISTAGE, "Clearing all context");
wglMakeCurrent (NULL, NULL);
}
else
{
ClutterBackendWin32 *backend_win32;
ClutterStageWin32 *stage_win32;
g_return_if_fail (impl != NULL);
CLUTTER_NOTE (MULTISTAGE, "Setting context for stage of type %s [%p]",
g_type_name (G_OBJECT_TYPE (impl)),
impl);
backend_win32 = CLUTTER_BACKEND_WIN32 (backend);
stage_win32 = CLUTTER_STAGE_WIN32 (impl);
/* no GL context to set */
if (backend_win32->gl_context == NULL)
return;
/* we might get here inside the final dispose cycle, so we
* need to handle this gracefully
*/
if (stage_win32->client_dc == NULL)
{
CLUTTER_NOTE (MULTISTAGE,
"Received a stale stage, clearing all context");
if (backend_win32->dummy_dc != NULL)
wglMakeCurrent (backend_win32->dummy_dc,
backend_win32->gl_context);
else
wglMakeCurrent (NULL, NULL);
}
else
{
CLUTTER_NOTE (BACKEND,
"MakeCurrent window %p (%s), context %p",
stage_win32->hwnd,
stage_win32->is_foreign_win ? "foreign" : "native",
backend_win32->gl_context);
wglMakeCurrent (stage_win32->client_dc,
backend_win32->gl_context);
}
}
}
static void
clutter_backend_win32_redraw (ClutterBackend *backend,
ClutterStage *stage)
{
ClutterStageWin32 *stage_win32;
ClutterStageWindow *impl;
impl = _clutter_stage_get_window (stage);
if (impl == NULL)
return;
g_return_if_fail (CLUTTER_IS_STAGE_WIN32 (impl));
stage_win32 = CLUTTER_STAGE_WIN32 (impl);
/* this will cause the stage implementation to be painted */
_clutter_stage_do_paint (stage, NULL);
cogl_flush ();
if (stage_win32->client_dc)
SwapBuffers (stage_win32->client_dc);
}
static ClutterStageWindow *
clutter_backend_win32_create_stage (ClutterBackend *backend,
ClutterStage *wrapper,
GError **error)
{
ClutterBackendWin32 *backend_win32 = CLUTTER_BACKEND_WIN32 (backend);
ClutterStageWin32 *stage_win32;
ClutterStageWindow *stage;
CLUTTER_NOTE (BACKEND, "Creating stage of type '%s'",
g_type_name (CLUTTER_STAGE_TYPE));
stage = g_object_new (CLUTTER_TYPE_STAGE_WIN32, NULL);
/* copy backend data into the stage */
stage_win32 = CLUTTER_STAGE_WIN32 (stage);
stage_win32->backend = backend_win32;
stage_win32->wrapper = wrapper;
return stage;
}
static ClutterDeviceManager *
clutter_backend_win32_get_device_manager (ClutterBackend *backend)
{
ClutterBackendWin32 *backend_win32 = CLUTTER_BACKEND_WIN32 (backend);
if (G_UNLIKELY (backend_win32->device_manager == NULL))
{
backend_win32->device_manager =
g_object_new (CLUTTER_TYPE_DEVICE_MANAGER_WIN32,
"backend", backend_win32,
NULL);
}
return backend_win32->device_manager;
}
static void
clutter_backend_win32_class_init (ClutterBackendWin32Class *klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
ClutterBackendClass *backend_class = CLUTTER_BACKEND_CLASS (klass);
gobject_class->constructor = clutter_backend_win32_constructor;
gobject_class->dispose = clutter_backend_win32_dispose;
gobject_class->finalize = clutter_backend_win32_finalize;
backend_class->pre_parse = clutter_backend_win32_pre_parse;
backend_class->init_events = clutter_backend_win32_init_events;
backend_class->create_stage = clutter_backend_win32_create_stage;
backend_class->add_options = clutter_backend_win32_add_options;
backend_class->get_features = clutter_backend_win32_get_features;
backend_class->redraw = clutter_backend_win32_redraw;
backend_class->create_context = clutter_backend_win32_create_context;
backend_class->ensure_context = clutter_backend_win32_ensure_context;
backend_class->get_device_manager = clutter_backend_win32_get_device_manager;
}
static void
clutter_backend_win32_init (ClutterBackendWin32 *backend_win32)
{
ClutterBackend *backend = CLUTTER_BACKEND (backend_win32);
backend_win32->gl_context = NULL;
backend_win32->no_event_retrieval = FALSE;
backend_win32->invisible_cursor = NULL;
/* FIXME: get from GetSystemMetric?
clutter_backend_set_double_click_time (backend, 250);
clutter_backend_set_double_click_distance (backend, 5);
clutter_backend_set_resolution (backend, 96.0);
*/
/* Set the maximum precision for Windows time functions. Without
this glib will not be able to sleep accurately enough to give a
reasonable frame rate */
timeBeginPeriod (1);
}
GType
_clutter_backend_impl_get_type (void)
{
return clutter_backend_win32_get_type ();
}
BOOL WINAPI
DllMain (HINSTANCE hinst, DWORD reason, LPVOID reserved)
{
if (reason == DLL_PROCESS_ATTACH)
/* Store the module handle so that we can use it to load resources */
clutter_hinst = hinst;
return TRUE;
}