Implement vsync for the new xrender backend

We use the Present extension for that, since it is the best option we
have.

Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>
This commit is contained in:
Yuxuan Shui 2019-01-01 14:23:51 +00:00
parent 6413ccbd71
commit 6d3ea3564b
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GPG Key ID: 37C999F617EA1A47
3 changed files with 100 additions and 40 deletions

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@ -34,6 +34,11 @@ typedef struct backend_info {
/// Optional /// Optional
void *(*root_change)(void *backend_data, session_t *ps); void *(*root_change)(void *backend_data, session_t *ps);
/// Called when vsync is toggled after initialization. If vsync is enabled when init()
/// is called, these function won't be called
void (*vsync_start)(void *backend_data, session_t *ps);
void (*vsync_stop)(void *backend_data, session_t *ps);
// =========== Rendering ============ // =========== Rendering ============
/// Called before any compose() calls. /// Called before any compose() calls.
@ -128,6 +133,9 @@ typedef struct backend_info {
/// Same logic as is_win_transparent applies here. /// Same logic as is_win_transparent applies here.
bool (*is_frame_transparent)(void *backend_data, win *w, void *win_data) bool (*is_frame_transparent)(void *backend_data, win *w, void *win_data)
__attribute__((nonnull(1, 2))); __attribute__((nonnull(1, 2)));
// =========== Hooks ============
/// Let the backend hook into the event handling queue
} backend_info_t; } backend_info_t;
extern backend_info_t xrender_backend; extern backend_info_t xrender_backend;

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@ -1,20 +1,28 @@
#include <assert.h> #include <assert.h>
#include <math.h> #include <math.h>
#include "common.h"
#include <xcb/present.h>
#include <xcb/sync.h>
#include "backend/backend.h" #include "backend/backend.h"
#include "backend_common.h" #include "backend_common.h"
#include "common.h"
#include "utils.h" #include "utils.h"
#include "win.h" #include "win.h"
#define auto __auto_type #define auto __auto_type
typedef struct _xrender_data { typedef struct _xrender_data {
/// The painting target drawable /// The idle fence for the present extension
xcb_drawable_t target_draw; xcb_sync_fence_t idle_fence;
/// The target window
xcb_window_t target_win;
/// The painting target, it is either the root or the overlay /// The painting target, it is either the root or the overlay
xcb_render_picture_t target; xcb_render_picture_t target;
/// A buffer of the image to paint /// A back buffer
xcb_render_picture_t target_buffer; xcb_render_picture_t back;
/// The corresponding pixmap to the back buffer
xcb_pixmap_t back_pixmap;
/// The original root window content, usually the wallpaper. /// The original root window content, usually the wallpaper.
/// We save it so we don't loss the wallpaper when we paint over /// We save it so we don't loss the wallpaper when we paint over
/// it. /// it.
@ -87,8 +95,7 @@ static void compose(void *backend_data, session_t *ps, win *w, void *win_data, i
// Mask out the region we don't want shadow on // Mask out the region we don't want shadow on
if (pixman_region32_not_empty(&ps->shadow_exclude_reg)) if (pixman_region32_not_empty(&ps->shadow_exclude_reg))
pixman_region32_subtract(&reg_tmp, &reg_tmp, pixman_region32_subtract(&reg_tmp, &reg_tmp, &ps->shadow_exclude_reg);
&ps->shadow_exclude_reg);
// Might be worth while to crop the region to shadow border // Might be worth while to crop the region to shadow border
pixman_region32_intersect_rect(&reg_tmp, &reg_tmp, w->g.x + w->shadow_dx, pixman_region32_intersect_rect(&reg_tmp, &reg_tmp, w->g.x + w->shadow_dx,
@ -120,10 +127,10 @@ static void compose(void *backend_data, session_t *ps, win *w, void *win_data, i
// Detect if the region is empty before painting // Detect if the region is empty before painting
if (pixman_region32_not_empty(&reg_tmp)) { if (pixman_region32_not_empty(&reg_tmp)) {
x_set_picture_clip_region(ps, xd->target_buffer, 0, 0, &reg_tmp); x_set_picture_clip_region(ps, xd->back, 0, 0, &reg_tmp);
xcb_render_composite( xcb_render_composite(
ps->c, XCB_RENDER_PICT_OP_OVER, wd->shadow_pict, alpha_pict, ps->c, XCB_RENDER_PICT_OP_OVER, wd->shadow_pict, alpha_pict,
xd->target_buffer, 0, 0, 0, 0, dst_x + w->shadow_dx, xd->back, 0, 0, 0, 0, dst_x + w->shadow_dx,
dst_y + w->shadow_dy, w->shadow_width, w->shadow_height); dst_y + w->shadow_dy, w->shadow_width, w->shadow_height);
} }
pixman_region32_fini(&reg_tmp); pixman_region32_fini(&reg_tmp);
@ -134,9 +141,9 @@ static void compose(void *backend_data, session_t *ps, win *w, void *win_data, i
// sure we get everything into the buffer // sure we get everything into the buffer
x_clear_picture_clip_region(ps, wd->rendered_pict); x_clear_picture_clip_region(ps, wd->rendered_pict);
x_set_picture_clip_region(ps, xd->target_buffer, 0, 0, reg_paint); x_set_picture_clip_region(ps, xd->back, 0, 0, reg_paint);
xcb_render_composite(ps->c, op, wd->rendered_pict, alpha_pict, xd->target_buffer, xcb_render_composite(ps->c, op, wd->rendered_pict, alpha_pict, xd->back, 0, 0, 0,
0, 0, 0, 0, dst_x, dst_y, w->widthb, w->heightb); 0, dst_x, dst_y, w->widthb, w->heightb);
} }
/** /**
@ -175,16 +182,16 @@ blur(void *backend_data, session_t *ps, double opacity, const region_t *reg_pain
// The multipass blur implemented here is not correct, but this is what old // The multipass blur implemented here is not correct, but this is what old
// compton did anyway. XXX // compton did anyway. XXX
xcb_render_picture_t src_pict = xd->target_buffer, dst_pict = tmp_picture[0]; xcb_render_picture_t src_pict = xd->back, dst_pict = tmp_picture[0];
auto alpha_pict = xd->alpha_pict[(int)(opacity * 255)]; auto alpha_pict = xd->alpha_pict[(int)(opacity * 255)];
int current = 0; int current = 0;
int src_x = reg->x1, src_y = reg->y1; int src_x = reg->x1, src_y = reg->y1;
// For more than 1 pass, we do: // For more than 1 pass, we do:
// target_buffer -(pass 1)-> tmp0 -(pass 2)-> tmp1 ... // back -(pass 1)-> tmp0 -(pass 2)-> tmp1 ...
// -(pass n-1)-> tmp0 or tmp1 -(pass n)-> target_buffer // -(pass n-1)-> tmp0 or tmp1 -(pass n)-> back
// For 1 pass, we do // For 1 pass, we do
// target_buffer -(pass 1)-> tmp0 -(copy)-> target_buffer // back -(pass 1)-> tmp0 -(copy)-> target_buffer
int i; int i;
for (i = 0; ps->o.blur_kerns[i]; i++) { for (i = 0; ps->o.blur_kerns[i]; i++) {
assert(i < MAX_BLUR_PASS - 1); assert(i < MAX_BLUR_PASS - 1);
@ -195,9 +202,9 @@ blur(void *backend_data, session_t *ps, double opacity, const region_t *reg_pain
// Copy from source picture to destination. The filter must // Copy from source picture to destination. The filter must
// be applied on source picture, to get the nearby pixels outside the // be applied on source picture, to get the nearby pixels outside the
// window. // window.
xcb_render_set_picture_filter( xcb_render_set_picture_filter(ps->c, src_pict, strlen(XRFILTER_CONVOLUTION),
ps->c, src_pict, strlen(XRFILTER_CONVOLUTION), XRFILTER_CONVOLUTION, XRFILTER_CONVOLUTION, kwid * khei + 2,
kwid * khei + 2, convolution_blur); convolution_blur);
if (ps->o.blur_kerns[i + 1] || i == 0) { if (ps->o.blur_kerns[i + 1] || i == 0) {
// This is not the last pass, or this is the first pass // This is not the last pass, or this is the first pass
@ -207,8 +214,8 @@ blur(void *backend_data, session_t *ps, double opacity, const region_t *reg_pain
} else { } else {
// This is the last pass, and this is also not the first // This is the last pass, and this is also not the first
xcb_render_composite(ps->c, XCB_RENDER_PICT_OP_OVER, src_pict, xcb_render_composite(ps->c, XCB_RENDER_PICT_OP_OVER, src_pict,
alpha_pict, xd->target_buffer, 0, 0, 0, 0, alpha_pict, xd->back, 0, 0, 0, 0, reg->x1,
reg->x1, reg->y1, width, height); reg->y1, width, height);
} }
xrfilter_reset(ps, src_pict); xrfilter_reset(ps, src_pict);
@ -223,8 +230,7 @@ blur(void *backend_data, session_t *ps, double opacity, const region_t *reg_pain
// There is only 1 pass // There is only 1 pass
if (i == 1) { if (i == 1) {
xcb_render_composite(ps->c, XCB_RENDER_PICT_OP_OVER, src_pict, alpha_pict, xcb_render_composite(ps->c, XCB_RENDER_PICT_OP_OVER, src_pict, alpha_pict,
xd->target_buffer, 0, 0, 0, 0, reg->x1, reg->y1, xd->back, 0, 0, 0, 0, reg->x1, reg->y1, width, height);
width, height);
} }
xcb_render_free_picture(ps->c, tmp_picture[0]); xcb_render_free_picture(ps->c, tmp_picture[0]);
@ -388,16 +394,26 @@ static void *init(session_t *ps) {
if (ps->overlay != XCB_NONE) { if (ps->overlay != XCB_NONE) {
xd->target = x_create_picture_with_visual_and_pixmap( xd->target = x_create_picture_with_visual_and_pixmap(
ps, ps->vis, ps->overlay, 0, NULL); ps, ps->vis, ps->overlay, 0, NULL);
xd->target_win = ps->overlay;
} else { } else {
xcb_render_create_picture_value_list_t pa = { xcb_render_create_picture_value_list_t pa = {
.subwindowmode = XCB_SUBWINDOW_MODE_INCLUDE_INFERIORS, .subwindowmode = XCB_SUBWINDOW_MODE_INCLUDE_INFERIORS,
}; };
xd->target = x_create_picture_with_visual_and_pixmap( xd->target = x_create_picture_with_visual_and_pixmap(
ps, ps->vis, ps->root, XCB_RENDER_CP_SUBWINDOW_MODE, &pa); ps, ps->vis, ps->root, XCB_RENDER_CP_SUBWINDOW_MODE, &pa);
xd->target_win = ps->root;
} }
xd->target_buffer = x_create_picture_with_visual( auto pictfmt = x_get_pictform_for_visual(ps, ps->vis);
ps, ps->root_width, ps->root_height, ps->vis, 0, NULL); if (!pictfmt) {
log_fatal("Default visual is invalid");
abort();
}
xd->back_pixmap =
x_create_pixmap(ps, pictfmt->depth, ps->root, ps->root_width, ps->root_height);
xd->back =
x_create_picture_with_pictfmt_and_pixmap(ps, pictfmt, xd->back_pixmap, 0, NULL);
xcb_pixmap_t root_pixmap = x_get_root_back_pixmap(ps); xcb_pixmap_t root_pixmap = x_get_root_back_pixmap(ps);
if (root_pixmap == XCB_NONE) { if (root_pixmap == XCB_NONE) {
@ -406,6 +422,20 @@ static void *init(session_t *ps) {
xd->root_pict = x_create_picture_with_visual_and_pixmap( xd->root_pict = x_create_picture_with_visual_and_pixmap(
ps, ps->vis, root_pixmap, 0, NULL); ps, ps->vis, root_pixmap, 0, NULL);
} }
if (ps->present_exists) {
xd->idle_fence = xcb_generate_id(ps->c);
// To make sure we won't get stuck waiting for the idle_fence, we maintain
// this invariant: the idle_fence is either triggered, or is in the
// process of being triggered (e.g. by xcb_present_pixmap)
auto e = xcb_request_check(
ps->c, xcb_sync_create_fence(ps->c, ps->root, xd->idle_fence, 1));
if (e) {
log_error("Cannot create a fence, vsync might not work");
xd->idle_fence = XCB_NONE;
free(e);
}
}
return xd; return xd;
} }
@ -423,29 +453,41 @@ static void *root_change(void *backend_data, session_t *ps) {
return init(ps); return init(ps);
} }
static void paint_root(void *backend_data, session_t *ps, const region_t *reg_paint) { static void prepare(void *backend_data, session_t *ps, const region_t *reg_paint) {
struct _xrender_data *xd = backend_data; struct _xrender_data *xd = backend_data;
if (ps->o.vsync != VSYNC_NONE && ps->present_exists) {
xcb_sync_await_fence(ps->c, 1, &xd->idle_fence);
}
// Paint the root pixmap (i.e. wallpaper)
// Limit the paint area // Limit the paint area
x_set_picture_clip_region(ps, xd->target_buffer, 0, 0, reg_paint); x_set_picture_clip_region(ps, xd->back, 0, 0, reg_paint);
xcb_render_composite(ps->c, XCB_RENDER_PICT_OP_SRC, xd->root_pict, XCB_NONE, xcb_render_composite(ps->c, XCB_RENDER_PICT_OP_SRC, xd->root_pict, XCB_NONE,
xd->target_buffer, 0, 0, 0, 0, 0, 0, ps->root_width, xd->back, 0, 0, 0, 0, 0, 0, ps->root_width, ps->root_height);
ps->root_height);
} }
static void present(void *backend_data, session_t *ps) { static void present(void *backend_data, session_t *ps) {
struct _xrender_data *xd = backend_data; struct _xrender_data *xd = backend_data;
if (ps->o.vsync != VSYNC_NONE && ps->present_exists) {
// Only reset the fence when we are sure we will trigger it again.
// To make sure rendering won't get stuck if user toggles vsync on the fly.
xcb_sync_reset_fence(ps->c, xd->idle_fence);
xcb_present_pixmap(ps->c, xd->target_win, xd->back_pixmap, 0, XCB_NONE,
XCB_NONE, 0, 0, XCB_NONE, XCB_NONE, xd->idle_fence, 0,
0, 1, 0, 0, NULL);
} else {
// compose() sets clip region, so clear it first to make // compose() sets clip region, so clear it first to make
// sure we update the whole screen. // sure we update the whole screen.
x_clear_picture_clip_region(ps, xd->target_buffer); x_clear_picture_clip_region(ps, xd->back);
// TODO buffer-age-like optimization might be possible here. // TODO buffer-age-like optimization might be possible here.
// but that will require a different backend API // but that will require a different backend API
xcb_render_composite(ps->c, XCB_RENDER_PICT_OP_SRC, xd->target_buffer, None, xcb_render_composite(ps->c, XCB_RENDER_PICT_OP_SRC, xd->back, None,
xd->target, 0, 0, 0, 0, 0, 0, ps->root_width, xd->target, 0, 0, 0, 0, 0, 0, ps->root_width,
ps->root_height); ps->root_height);
}
} }
struct backend_info xrender_backend = { struct backend_info xrender_backend = {
@ -453,7 +495,7 @@ struct backend_info xrender_backend = {
.deinit = deinit, .deinit = deinit,
.blur = blur, .blur = blur,
.present = present, .present = present,
.prepare = paint_root, .prepare = prepare,
.compose = compose, .compose = compose,
.root_change = root_change, .root_change = root_change,
.render_win = render_win, .render_win = render_win,
@ -462,3 +504,5 @@ struct backend_info xrender_backend = {
.is_win_transparent = default_is_win_transparent, .is_win_transparent = default_is_win_transparent,
.is_frame_transparent = default_is_frame_transparent, .is_frame_transparent = default_is_frame_transparent,
}; };
// vim: set noet sw=8 ts=8:

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@ -2869,8 +2869,16 @@ session_init(session_t *ps_old, int argc, char **argv) {
ext_info = xcb_get_extension_data(ps->c, &xcb_present_id); ext_info = xcb_get_extension_data(ps->c, &xcb_present_id);
if (ext_info && ext_info->present) { if (ext_info && ext_info->present) {
auto r =
xcb_present_query_version_reply(ps->c,
xcb_present_query_version(ps->c,
XCB_PRESENT_MAJOR_VERSION,
XCB_PRESENT_MINOR_VERSION),
NULL);
if (r) {
ps->present_exists = true; ps->present_exists = true;
} }
}
// Query X Sync // Query X Sync
ext_info = xcb_get_extension_data(ps->c, &xcb_sync_id); ext_info = xcb_get_extension_data(ps->c, &xcb_sync_id);