screenshooter: Grab pixel data directly before buffer swap

diff --git a/clients/screenshot.c b/clients/screenshot.c
index 086ddd9..328d106 100644 (file)
--- a/clients/screenshot.c
+++ b/clients/screenshot.c
@@ -41,6 +41,7 @@
 static struct wl_shm *shm;
 static struct screenshooter *screenshooter;
 static struct wl_list output_list;
+int buffer_copy_done;
 
 struct screenshooter_output {
        struct wl_output *output;
@@ -94,6 +95,16 @@ static const struct wl_output_listener output_listener = {
 };
 
 static void
+screenshot_done(void *data, struct screenshooter *screenshooter)
+{
+       buffer_copy_done = 1;
+}
+
+static const struct screenshooter_listener screenshooter_listener = {
+       screenshot_done
+};
+
+static void
 handle_global(struct wl_display *display, uint32_t id,
              const char *interface, uint32_t version, void *data)
 {
@@ -188,6 +199,9 @@ int main(int argc, char *argv[])
                return -1;
        }
 
+       screenshooter_add_listener(screenshooter, &screenshooter_listener, screenshooter);
+
+
        wl_list_for_each(output, &output_list, link) {
                width = MAX(width, output->offset_x + output->width);
                height = MAX(height, output->offset_y + output->height);
@@ -197,11 +211,12 @@ int main(int argc, char *argv[])
 
        wl_list_for_each_safe(output, next, &output_list, link) {
                screenshooter_shoot(screenshooter, output->output, buffer);
+               buffer_copy_done = 0;
+               while (!buffer_copy_done)
+                       wl_display_roundtrip(display);
                free(output);
        }
 
-       wl_display_roundtrip(display);
-
        write_png(width, height, data);
 
        return 0;

diff --git a/protocol/screenshooter.xml b/protocol/screenshooter.xml
index 1487c6d..76e3c85 100644 (file)
--- a/protocol/screenshooter.xml
+++ b/protocol/screenshooter.xml
@@ -5,6 +5,8 @@
       <arg name="output" type="object" interface="wl_output"/>
       <arg name="buffer" type="object" interface="wl_buffer"/>
     </request>
+    <event name="done">
+    </event>
   </interface>
 
 </protocol>

diff --git a/src/compositor-drm.c b/src/compositor-drm.c
index 837da8c..dcd5e99 100644 (file)
--- a/src/compositor-drm.c
+++ b/src/compositor-drm.c
@@ -215,6 +215,8 @@ drm_output_render(struct drm_output *output, pixman_region32_t *damage)
        wl_list_for_each_reverse(surface, &compositor->base.surface_list, link)
                weston_surface_draw(surface, &output->base, damage);
 
+       weston_output_do_read_pixels(&output->base);
+
        eglSwapBuffers(compositor->base.display, output->egl_surface);
        output->next_bo = gbm_surface_lock_front_buffer(output->surface);
        if (!output->next_bo) {
@@ -1190,21 +1192,6 @@ drm_set_dpms(struct weston_output *output_base, enum dpms_enum level)
        drmModeFreeConnector(connector);
 }
 
-static void
-drm_output_read_pixels(struct weston_output *output_base, void *data)
-{
-       struct drm_output *output = (struct drm_output *) output_base;
-       struct drm_compositor *compositor =
-               (struct drm_compositor *) output->base.compositor;
-
-       eglMakeCurrent(compositor->base.display, output->egl_surface,
-                       output->egl_surface, compositor->base.context);
-
-       glReadPixels(0, 0, output_base->current->width,
-                    output_base->current->height,
-                    compositor->base.read_format, GL_UNSIGNED_BYTE, data);
-}
-
 static int
 create_output_for_connector(struct drm_compositor *ec,
                            drmModeRes *resources,
@@ -1313,7 +1300,6 @@ create_output_for_connector(struct drm_compositor *ec,
        output->base.repaint = drm_output_repaint;
        output->base.destroy = drm_output_destroy;
        output->base.assign_planes = drm_assign_planes;
-       output->base.read_pixels = drm_output_read_pixels;
        output->base.set_dpms = drm_set_dpms;
        output->base.switch_mode = drm_output_switch_mode;
 

diff --git a/src/compositor-wayland.c b/src/compositor-wayland.c
index afd9121..3260c8e 100644 (file)
--- a/src/compositor-wayland.c
+++ b/src/compositor-wayland.c
@@ -357,6 +357,8 @@ wayland_output_repaint(struct weston_output *output_base,
 
        draw_border(output);
 
+       weston_output_do_read_pixels(&output->base);
+
        eglSwapBuffers(compositor->base.display, output->egl_surface);
        callback = wl_surface_frame(output->parent.surface);
        wl_callback_add_listener(callback, &frame_listener, output);
@@ -377,21 +379,6 @@ wayland_output_destroy(struct weston_output *output_base)
        return;
 }
 
-static void
-wayland_output_read_pixels(struct weston_output *output_base, void *data)
-{
-       struct wayland_output *output = (struct wayland_output *) output_base;
-       struct wayland_compositor *compositor =
-               (struct wayland_compositor *) output->base.compositor;
-
-       eglMakeCurrent(compositor->base.display, output->egl_surface,
-                       output->egl_surface, compositor->base.context);
-
-       glReadPixels(0, 0, output_base->current->width,
-                    output_base->current->height,
-                    compositor->base.read_format, GL_UNSIGNED_BYTE, data);
-}
-
 static int
 wayland_compositor_create_output(struct wayland_compositor *c,
                                 int width, int height)
@@ -460,7 +447,6 @@ wayland_compositor_create_output(struct wayland_compositor *c,
        output->base.repaint = wayland_output_repaint;
        output->base.destroy = wayland_output_destroy;
        output->base.assign_planes = NULL;
-       output->base.read_pixels = wayland_output_read_pixels;
        output->base.set_backlight = NULL;
        output->base.set_dpms = NULL;
        output->base.switch_mode = NULL;

diff --git a/src/compositor-x11.c b/src/compositor-x11.c
index b910831..6d9bb0e 100644 (file)
--- a/src/compositor-x11.c
+++ b/src/compositor-x11.c
@@ -212,6 +212,8 @@ x11_output_repaint(struct weston_output *output_base,
        wl_list_for_each_reverse(surface, &compositor->base.surface_list, link)
                weston_surface_draw(surface, &output->base, damage);
 
+       weston_output_do_read_pixels(&output->base);
+
        eglSwapBuffers(compositor->base.display, output->egl_surface);
 
        wl_event_source_timer_update(output->finish_frame_timer, 10);
@@ -344,21 +346,6 @@ x11_output_set_icon(struct x11_compositor *c,
        pixman_image_unref(image);
 }
 
-static void
-x11_output_read_pixels(struct weston_output *output_base, void *data)
-{
-       struct x11_output *output = (struct x11_output *) output_base;
-       struct x11_compositor *compositor =
-               (struct x11_compositor *) output->base.compositor;
-
-       eglMakeCurrent(compositor->base.display, output->egl_surface,
-                       output->egl_surface, compositor->base.context);
-
-       glReadPixels(0, 0, output_base->current->width,
-                    output_base->current->height,
-                    compositor->base.read_format, GL_UNSIGNED_BYTE, data);
-}
-
 static int
 x11_compositor_create_output(struct x11_compositor *c, int x, int y,
                             int width, int height, int fullscreen)
@@ -470,7 +457,6 @@ x11_compositor_create_output(struct x11_compositor *c, int x, int y,
        output->base.repaint = x11_output_repaint;
        output->base.destroy = x11_output_destroy;
        output->base.assign_planes = NULL;
-       output->base.read_pixels = x11_output_read_pixels;
        output->base.set_backlight = NULL;
        output->base.set_dpms = NULL;
        output->base.switch_mode = NULL;

diff --git a/src/compositor.c b/src/compositor.c
index ddbc077..2b46fbc 100644 (file)
--- a/src/compositor.c
+++ b/src/compositor.c
@@ -2389,6 +2389,7 @@ weston_output_init(struct weston_output *output, struct weston_compositor *c,
        output->mm_width = width;
        output->mm_height = height;
        output->dirty = 1;
+       wl_list_init(&output->read_pixels_list);
 
        output->zoom.active = 0;
        output->zoom.increment = 0.05;
@@ -2412,6 +2413,20 @@ weston_output_init(struct weston_output *output, struct weston_compositor *c,
                                      output, bind_output);
 }
 
+WL_EXPORT void
+weston_output_do_read_pixels(struct weston_output *output)
+{
+       struct weston_read_pixels *r, *next;
+
+       glPixelStorei(GL_PACK_ALIGNMENT, 1);
+       wl_list_for_each_safe(r, next, &output->read_pixels_list, link) {
+               glReadPixels(r->x, r->y, r->width, r->height,
+                            output->compositor->read_format,
+                            GL_UNSIGNED_BYTE, r->data);
+               r->done(r, output);
+       }
+}
+
 static void
 compositor_bind(struct wl_client *client,
                void *data, uint32_t version, uint32_t id)

diff --git a/src/compositor.h b/src/compositor.h
index 648b045..59494ad 100644 (file)
--- a/src/compositor.h
+++ b/src/compositor.h
@@ -44,6 +44,7 @@ struct weston_transform {
 
 struct weston_surface;
 struct weston_input_device;
+struct weston_output;
 
 struct weston_mode {
        uint32_t flags;
@@ -72,6 +73,14 @@ enum dpms_enum {
        WESTON_DPMS_OFF
 };
 
+struct weston_read_pixels {
+       void *data;
+       int x, y, width, height;
+       void (*done)(struct weston_read_pixels *read_pixels,
+                    struct weston_output *output);
+       struct wl_list link;
+};
+
 struct weston_output {
        uint32_t id;
 
@@ -90,6 +99,7 @@ struct weston_output {
        int repaint_scheduled;
        struct weston_output_zoom zoom;
        int dirty;
+       struct wl_list read_pixels_list;
 
        char *make, *model;
        uint32_t subpixel;
@@ -102,7 +112,6 @@ struct weston_output {
                        pixman_region32_t *damage);
        void (*destroy)(struct weston_output *output);
        void (*assign_planes)(struct weston_output *output);
-       void (*read_pixels)(struct weston_output *output, void *data);
        int (*switch_mode)(struct weston_output *output, struct weston_mode *mode);
 
        /* backlight values are on 0-255 range, where higher is brighter */
@@ -424,6 +433,8 @@ weston_output_finish_frame(struct weston_output *output, int msecs);
 void
 weston_output_damage(struct weston_output *output);
 void
+weston_output_do_read_pixels(struct weston_output *output);
+void
 weston_compositor_repick(struct weston_compositor *compositor);
 void
 weston_compositor_schedule_repaint(struct weston_compositor *compositor);

diff --git a/src/screenshooter.c b/src/screenshooter.c
index b4b341b..7ba475d 100644 (file)
--- a/src/screenshooter.c
+++ b/src/screenshooter.c
@@ -36,6 +36,12 @@ struct screenshooter {
        struct wl_listener destroy_listener;
 };
 
+struct screenshooter_read_pixels {
+       struct weston_read_pixels base;
+       struct wl_buffer *buffer;
+       struct wl_resource *resource;
+};
+
 static void
 copy_bgra_yflip(uint8_t *dst, uint8_t *src, int height,
                int dst_stride, int src_stride)
@@ -82,15 +88,52 @@ copy_rgba_yflip(uint8_t *dst, uint8_t *src, int height,
 }
 
 static void
+screenshooter_read_pixels_done(struct weston_read_pixels *base,
+                              struct weston_output *output)
+{
+       struct screenshooter_read_pixels *r =
+               (struct screenshooter_read_pixels *) base;
+       int32_t buffer_stride, output_stride;
+       uint8_t *d, *s;
+
+       buffer_stride = wl_shm_buffer_get_stride(r->buffer);
+       output_stride = output->current->width * 4;
+
+       d = wl_shm_buffer_get_data(r->buffer) +
+               output->y * buffer_stride + output->x * 4;
+       s = r->base.data + output_stride * (output->current->height - 1);
+
+       switch (output->compositor->read_format) {
+       case GL_BGRA_EXT:
+               copy_bgra_yflip(d, s, output->current->height,
+                               buffer_stride, output_stride);
+               break;
+       case GL_RGBA:
+               copy_rgba_yflip(d, s, output->current->height,
+                               buffer_stride, output_stride);
+               break;
+       default:
+               break;
+       }
+
+       wl_list_remove(&r->base.link);
+
+       screenshooter_send_done(r->resource);
+       free(r->base.data);
+       free(r);
+
+}
+
+static void
 screenshooter_shoot(struct wl_client *client,
                    struct wl_resource *resource,
                    struct wl_resource *output_resource,
                    struct wl_resource *buffer_resource)
 {
        struct weston_output *output = output_resource->data;
+       struct screenshooter_read_pixels *r;
        struct wl_buffer *buffer = buffer_resource->data;
-       uint8_t *tmp, *d, *s;
-       int32_t buffer_stride, output_stride;
+       int32_t stride;
 
        if (!wl_buffer_is_shm(buffer))
                return;
@@ -99,35 +142,30 @@ screenshooter_shoot(struct wl_client *client,
            buffer->height < output->current->height)
                return;
 
-       buffer_stride = wl_shm_buffer_get_stride(buffer);
-       output_stride = output->current->width * 4;
-       tmp = malloc(output_stride * output->current->height);
-       if (tmp == NULL) {
+       r = malloc(sizeof *r);
+       if (r == NULL) {
                wl_resource_post_no_memory(resource);
                return;
        }
 
-       glPixelStorei(GL_PACK_ALIGNMENT, 1);
-       output->read_pixels(output, tmp);
-
-       d = wl_shm_buffer_get_data(buffer) + output->y * buffer_stride +
-                                                       output->x * 4;
-       s = tmp + output_stride * (output->current->height - 1);
-
-       switch (output->compositor->read_format) {
-       case GL_BGRA_EXT:
-               copy_bgra_yflip(d, s, output->current->height,
-                               buffer_stride, output_stride);
-               break;
-       case GL_RGBA:
-               copy_rgba_yflip(d, s, output->current->height,
-                               buffer_stride, output_stride);
-               break;
-       default:
-               break;
+       r->base.x = 0;
+       r->base.y = 0;
+       r->base.width = output->current->width;
+       r->base.height = output->current->height;
+       r->base.done = screenshooter_read_pixels_done;
+       r->buffer = buffer;
+       r->resource = resource;
+       stride = buffer->width * 4;
+       r->base.data = malloc(stride * buffer->height);
+
+       if (r->base.data == NULL) {
+               free(r);
+               wl_resource_post_no_memory(resource);
+               return;
        }
 
-       free(tmp);
+       wl_list_insert(output->read_pixels_list.prev, &r->base.link);
+       weston_compositor_schedule_repaint(output->compositor);
 }
 
 struct screenshooter_interface screenshooter_implementation = {