clutter/stage-view: Add tile based shadow damage detection

Compare, tile by tile, whether actual damage actually changed any
pixels. While this requires mmap():ing DMA buffers and comparing their
content, we should only ever use shadow buffers when we're using the
software renderer, meaning mmap() is cheap as it doesn't involve any
downloading.

This works by making the shadow framebuffer double buffered, while
keeping track of damage history. When we're about to swap the onscreen
buffer, we compare what part of the posted damage actually changed,
records that into a damage history, then given the onscreen buffer age,
collect all actual damage for that age. The intersection of these tiles,
and the actual damage, is then used when blitting the shadow buffer to
the onscreen framebuffer.

Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1157

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1237
This commit is contained in:
Jonas Ådahl 2020-05-06 22:14:17 +02:00 committed by Georges Basile Stavracas Neto
parent f8daa6bc70
commit c2c4f74923

View File

@ -23,6 +23,7 @@
#include <cairo-gobject.h>
#include <math.h>
#include "clutter/clutter-damage-history.h"
#include "clutter/clutter-private.h"
#include "clutter/clutter-mutter.h"
#include "cogl/cogl.h"
@ -56,6 +57,12 @@ typedef struct _ClutterStageViewPrivate
gboolean use_shadowfb;
struct {
struct {
CoglDmaBufHandle *handles[2];
int current_idx;
ClutterDamageHistory *damage_history;
} dma_buf;
CoglOffscreen *framebuffer;
} shadow;
@ -268,6 +275,66 @@ paint_transformed_framebuffer (ClutterStageView *view,
cogl_framebuffer_pop_matrix (dst_framebuffer);
}
static gboolean
is_shadowfb_double_buffered (ClutterStageView *view)
{
ClutterStageViewPrivate *priv =
clutter_stage_view_get_instance_private (view);
return priv->shadow.dma_buf.handles[0] && priv->shadow.dma_buf.handles[1];
}
static gboolean
init_dma_buf_shadowfbs (ClutterStageView *view,
CoglContext *cogl_context,
int width,
int height,
GError **error)
{
ClutterStageViewPrivate *priv =
clutter_stage_view_get_instance_private (view);
CoglRenderer *cogl_renderer = cogl_context_get_renderer (cogl_context);
CoglFramebuffer *initial_shadowfb;
if (!cogl_clutter_winsys_has_feature (COGL_WINSYS_FEATURE_BUFFER_AGE))
{
g_set_error (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
"Buffer age not supported");
return FALSE;
}
if (!cogl_is_onscreen (priv->framebuffer))
{
g_set_error (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
"Tried to use shadow buffer without onscreen");
return FALSE;
}
priv->shadow.dma_buf.handles[0] = cogl_renderer_create_dma_buf (cogl_renderer,
width, height,
error);
if (!priv->shadow.dma_buf.handles[0])
return FALSE;
priv->shadow.dma_buf.handles[1] = cogl_renderer_create_dma_buf (cogl_renderer,
width, height,
error);
if (!priv->shadow.dma_buf.handles[1])
{
g_clear_pointer (&priv->shadow.dma_buf.handles[0],
cogl_dma_buf_handle_free);
return FALSE;
}
priv->shadow.dma_buf.damage_history = clutter_damage_history_new ();
initial_shadowfb =
cogl_dma_buf_handle_get_framebuffer (priv->shadow.dma_buf.handles[0]);
priv->shadow.framebuffer = cogl_object_ref (initial_shadowfb);
return TRUE;
}
static CoglOffscreen *
create_offscreen_framebuffer (CoglContext *context,
int width,
@ -299,7 +366,7 @@ create_offscreen_framebuffer (CoglContext *context,
}
static gboolean
init_offscreen_shadowfb (ClutterStageView *view,
init_fallback_shadowfb (ClutterStageView *view,
CoglContext *cogl_context,
int width,
int height,
@ -331,7 +398,17 @@ init_shadowfb (ClutterStageView *view)
height = cogl_framebuffer_get_height (priv->framebuffer);
cogl_context = cogl_framebuffer_get_context (priv->framebuffer);
if (!init_offscreen_shadowfb (view, cogl_context, width, height, &error))
if (init_dma_buf_shadowfbs (view, cogl_context, width, height, &error))
{
g_message ("Initialized double buffered shadow fb for %s", priv->name);
return;
}
g_warning ("Failed to initialize double buffered shadow fb for %s: %s",
priv->name, error->message);
g_clear_error (&error);
if (!init_fallback_shadowfb (view, cogl_context, width, height, &error))
{
g_warning ("Failed to initialize single buffered shadow fb for %s: %s",
priv->name, error->message);
@ -372,42 +449,259 @@ clutter_stage_view_after_paint (ClutterStageView *view,
}
}
void
clutter_stage_view_before_swap_buffer (ClutterStageView *view,
static gboolean
is_tile_dirty (cairo_rectangle_int_t *tile,
uint8_t *current_data,
uint8_t *prev_data,
int bpp,
int stride)
{
int y;
for (y = tile->y; y < tile->y + tile->height; y++)
{
if (memcmp (prev_data + y * stride + tile->x * bpp,
current_data + y * stride + tile->x * bpp,
tile->width * bpp) != 0)
return TRUE;
}
return FALSE;
}
static int
flip_dma_buf_idx (int idx)
{
return (idx + 1) % 2;
}
static cairo_region_t *
find_damaged_tiles (ClutterStageView *view,
const cairo_region_t *damage_region,
GError **error)
{
ClutterStageViewPrivate *priv =
clutter_stage_view_get_instance_private (view);
cairo_region_t *tile_damage_region;
cairo_rectangle_int_t damage_extents;
cairo_rectangle_int_t fb_rect;
int prev_dma_buf_idx;
CoglDmaBufHandle *prev_dma_buf_handle;
uint8_t *prev_data;
int current_dma_buf_idx;
CoglDmaBufHandle *current_dma_buf_handle;
uint8_t *current_data;
int width, height, stride, bpp;
int tile_x_min, tile_x_max;
int tile_y_min, tile_y_max;
int tile_x, tile_y;
const int tile_size = 16;
prev_dma_buf_idx = flip_dma_buf_idx (priv->shadow.dma_buf.current_idx);
prev_dma_buf_handle = priv->shadow.dma_buf.handles[prev_dma_buf_idx];
current_dma_buf_idx = priv->shadow.dma_buf.current_idx;
current_dma_buf_handle = priv->shadow.dma_buf.handles[current_dma_buf_idx];
width = cogl_dma_buf_handle_get_width (current_dma_buf_handle);
height = cogl_dma_buf_handle_get_height (current_dma_buf_handle);
stride = cogl_dma_buf_handle_get_stride (current_dma_buf_handle);
bpp = cogl_dma_buf_handle_get_bpp (current_dma_buf_handle);
cogl_framebuffer_finish (priv->shadow.framebuffer);
if (!cogl_dma_buf_handle_sync_read_start (prev_dma_buf_handle, error))
return NULL;
if (!cogl_dma_buf_handle_sync_read_start (current_dma_buf_handle, error))
goto err_sync_read_current;
prev_data = cogl_dma_buf_handle_mmap (prev_dma_buf_handle, error);
if (!prev_data)
goto err_mmap_prev;
current_data = cogl_dma_buf_handle_mmap (current_dma_buf_handle, error);
if (!current_data)
goto err_mmap_current;
fb_rect = (cairo_rectangle_int_t) {
.width = width,
.height = height,
};
cairo_region_get_extents (damage_region, &damage_extents);
tile_x_min = damage_extents.x / tile_size;
tile_x_max = ((damage_extents.x + damage_extents.width + tile_size - 1) /
tile_size);
tile_y_min = damage_extents.y / tile_size;
tile_y_max = ((damage_extents.y + damage_extents.height + tile_size - 1) /
tile_size);
tile_damage_region = cairo_region_create ();
for (tile_y = tile_y_min; tile_y <= tile_y_max; tile_y++)
{
for (tile_x = tile_x_min; tile_x <= tile_x_max; tile_x++)
{
cairo_rectangle_int_t tile = {
.x = tile_x * tile_size,
.y = tile_y * tile_size,
.width = tile_size,
.height = tile_size,
};
if (cairo_region_contains_rectangle (damage_region, &tile) ==
CAIRO_REGION_OVERLAP_OUT)
continue;
_clutter_util_rectangle_intersection (&tile, &fb_rect, &tile);
if (is_tile_dirty (&tile, current_data, prev_data, bpp, stride))
cairo_region_union_rectangle (tile_damage_region, &tile);
}
}
if (!cogl_dma_buf_handle_sync_read_end (prev_dma_buf_handle, error))
{
g_warning ("Failed to end DMA buffer read synchronization: %s",
(*error)->message);
g_clear_error (error);
}
if (!cogl_dma_buf_handle_sync_read_end (current_dma_buf_handle, error))
{
g_warning ("Failed to end DMA buffer read synchronization: %s",
(*error)->message);
g_clear_error (error);
}
cogl_dma_buf_handle_munmap (prev_dma_buf_handle, prev_data, NULL);
cogl_dma_buf_handle_munmap (current_dma_buf_handle, current_data, NULL);
cairo_region_intersect (tile_damage_region, damage_region);
return tile_damage_region;
err_mmap_current:
cogl_dma_buf_handle_munmap (prev_dma_buf_handle, prev_data, NULL);
err_mmap_prev:
cogl_dma_buf_handle_sync_read_end (current_dma_buf_handle, NULL);
err_sync_read_current:
cogl_dma_buf_handle_sync_read_end (prev_dma_buf_handle, NULL);
return NULL;
}
static void
swap_dma_buf_framebuffer (ClutterStageView *view)
{
ClutterStageViewPrivate *priv =
clutter_stage_view_get_instance_private (view);
int next_idx;
CoglDmaBufHandle *next_dma_buf_handle;
CoglOffscreen *next_framebuffer;
next_idx = ((priv->shadow.dma_buf.current_idx + 1) %
G_N_ELEMENTS (priv->shadow.dma_buf.handles));
priv->shadow.dma_buf.current_idx = next_idx;
next_dma_buf_handle = priv->shadow.dma_buf.handles[next_idx];
next_framebuffer =
cogl_dma_buf_handle_get_framebuffer (next_dma_buf_handle);
cogl_clear_object (&priv->shadow.framebuffer);
priv->shadow.framebuffer = cogl_object_ref (next_framebuffer);
}
static void
copy_shadowfb_to_onscreen (ClutterStageView *view,
const cairo_region_t *swap_region)
{
ClutterStageViewPrivate *priv =
clutter_stage_view_get_instance_private (view);
g_autoptr (GError) error = NULL;
if (!priv->shadow.framebuffer)
return;
ClutterDamageHistory *damage_history = priv->shadow.dma_buf.damage_history;
cairo_region_t *damage_region;
int age;
int i;
if (cairo_region_is_empty (swap_region))
{
int width, height;
width = cogl_framebuffer_get_width (priv->framebuffer);
height = cogl_framebuffer_get_height (priv->framebuffer);
if (!cogl_blit_framebuffer (priv->shadow.framebuffer,
priv->framebuffer,
0, 0,
0, 0,
width, height,
&error))
g_warning ("Failed to blit shadow buffer: %s", error->message);
cairo_rectangle_int_t full_damage = {
.width = cogl_framebuffer_get_width (priv->framebuffer),
.height = cogl_framebuffer_get_height (priv->framebuffer),
};
damage_region = cairo_region_create_rectangle (&full_damage);
}
else
{
int n_rects;
int i;
damage_region = cairo_region_copy (swap_region);
}
n_rects = cairo_region_num_rectangles (swap_region);
for (i = 0; i < n_rects; i++)
if (is_shadowfb_double_buffered (view))
{
CoglOnscreen *onscreen = COGL_ONSCREEN (priv->framebuffer);
cairo_region_t *changed_region;
if (cogl_onscreen_get_frame_counter (onscreen) >= 1)
{
g_autoptr (GError) error = NULL;
changed_region = find_damaged_tiles (view, damage_region, &error);
if (!changed_region)
{
int other_dma_buf_idx;
g_warning ("Disabling actual damage detection: %s",
error->message);
other_dma_buf_idx =
flip_dma_buf_idx (priv->shadow.dma_buf.current_idx);
g_clear_pointer (&priv->shadow.dma_buf.handles[other_dma_buf_idx],
cogl_dma_buf_handle_free);
}
}
else
{
changed_region = cairo_region_copy (damage_region);
}
if (changed_region)
{
int buffer_age;
clutter_damage_history_record (damage_history, changed_region);
buffer_age = cogl_onscreen_get_buffer_age (onscreen);
if (clutter_damage_history_is_age_valid (damage_history, buffer_age))
{
for (age = 1; age <= buffer_age; age++)
{
const cairo_region_t *old_damage;
old_damage = clutter_damage_history_lookup (damage_history, age);
cairo_region_union (changed_region, old_damage);
}
cairo_region_destroy (damage_region);
damage_region = g_steal_pointer (&changed_region);
}
else
{
cairo_region_destroy (changed_region);
}
clutter_damage_history_step (damage_history);
}
}
for (i = 0; i < cairo_region_num_rectangles (damage_region); i++)
{
g_autoptr (GError) error = NULL;
cairo_rectangle_int_t rect;
cairo_region_get_rectangle (swap_region, i, &rect);
cairo_region_get_rectangle (damage_region, i, &rect);
if (!cogl_blit_framebuffer (priv->shadow.framebuffer,
priv->framebuffer,
rect.x, rect.y,
@ -416,10 +710,26 @@ clutter_stage_view_before_swap_buffer (ClutterStageView *view,
&error))
{
g_warning ("Failed to blit shadow buffer: %s", error->message);
cairo_region_destroy (damage_region);
return;
}
}
}
cairo_region_destroy (damage_region);
if (is_shadowfb_double_buffered (view))
swap_dma_buf_framebuffer (view);
}
void
clutter_stage_view_before_swap_buffer (ClutterStageView *view,
const cairo_region_t *swap_region)
{
ClutterStageViewPrivate *priv =
clutter_stage_view_get_instance_private (view);
if (priv->shadow.framebuffer)
copy_shadowfb_to_onscreen (view, swap_region);
}
float
@ -431,6 +741,47 @@ clutter_stage_view_get_scale (ClutterStageView *view)
return priv->scale;
}
typedef void (*FrontBufferCallback) (CoglFramebuffer *framebuffer,
gconstpointer user_data);
static void
clutter_stage_view_foreach_front_buffer (ClutterStageView *view,
FrontBufferCallback callback,
gconstpointer user_data)
{
ClutterStageViewPrivate *priv =
clutter_stage_view_get_instance_private (view);
if (priv->offscreen)
{
callback (priv->offscreen, user_data);
}
else if (priv->shadow.framebuffer)
{
if (is_shadowfb_double_buffered (view))
{
int i;
for (i = 0; i < G_N_ELEMENTS (priv->shadow.dma_buf.handles); i++)
{
CoglDmaBufHandle *handle = priv->shadow.dma_buf.handles[i];
CoglFramebuffer *framebuffer =
cogl_dma_buf_handle_get_framebuffer (handle);
callback (framebuffer, user_data);
}
}
else
{
callback (priv->shadow.framebuffer, user_data);
}
}
else
{
callback (priv->framebuffer, user_data);
}
}
gboolean
clutter_stage_view_is_dirty_viewport (ClutterStageView *view)
{
@ -449,6 +800,19 @@ clutter_stage_view_invalidate_viewport (ClutterStageView *view)
priv->dirty_viewport = TRUE;
}
static void
set_framebuffer_viewport (CoglFramebuffer *framebuffer,
gconstpointer user_data)
{
const graphene_rect_t *rect = user_data;
cogl_framebuffer_set_viewport (framebuffer,
rect->origin.x,
rect->origin.y,
rect->size.width,
rect->size.height);
}
void
clutter_stage_view_set_viewport (ClutterStageView *view,
float x,
@ -458,11 +822,17 @@ clutter_stage_view_set_viewport (ClutterStageView *view,
{
ClutterStageViewPrivate *priv =
clutter_stage_view_get_instance_private (view);
CoglFramebuffer *framebuffer;
graphene_rect_t rect;
priv->dirty_viewport = FALSE;
framebuffer = clutter_stage_view_get_framebuffer (view);
cogl_framebuffer_set_viewport (framebuffer, x, y, width, height);
rect = (graphene_rect_t) {
.origin = { .x = x, .y = y },
.size = { .width = width, .height = height },
};
clutter_stage_view_foreach_front_buffer (view,
set_framebuffer_viewport,
&rect);
}
gboolean
@ -474,6 +844,13 @@ clutter_stage_view_is_dirty_projection (ClutterStageView *view)
return priv->dirty_projection;
}
static void
set_framebuffer_projection_matrix (CoglFramebuffer *framebuffer,
gconstpointer user_data)
{
cogl_framebuffer_set_projection_matrix (framebuffer, user_data);
}
void
clutter_stage_view_invalidate_projection (ClutterStageView *view)
{
@ -489,11 +866,11 @@ clutter_stage_view_set_projection (ClutterStageView *view,
{
ClutterStageViewPrivate *priv =
clutter_stage_view_get_instance_private (view);
CoglFramebuffer *framebuffer;
priv->dirty_projection = FALSE;
framebuffer = clutter_stage_view_get_framebuffer (view);
cogl_framebuffer_set_projection_matrix (framebuffer, matrix);
clutter_stage_view_foreach_front_buffer (view,
set_framebuffer_projection_matrix,
matrix);
}
void
@ -716,10 +1093,20 @@ clutter_stage_view_dispose (GObject *object)
ClutterStageView *view = CLUTTER_STAGE_VIEW (object);
ClutterStageViewPrivate *priv =
clutter_stage_view_get_instance_private (view);
int i;
g_clear_pointer (&priv->name, g_free);
g_clear_pointer (&priv->framebuffer, cogl_object_unref);
g_clear_pointer (&priv->shadow.framebuffer, cogl_object_unref);
for (i = 0; i < G_N_ELEMENTS (priv->shadow.dma_buf.handles); i++)
{
g_clear_pointer (&priv->shadow.dma_buf.handles[i],
cogl_dma_buf_handle_free);
}
g_clear_pointer (&priv->shadow.dma_buf.damage_history,
clutter_damage_history_free);
g_clear_pointer (&priv->offscreen, cogl_object_unref);
g_clear_pointer (&priv->offscreen_pipeline, cogl_object_unref);
g_clear_pointer (&priv->redraw_clip, cairo_region_destroy);