Use wlr-export-dmabuf to capture frames

README.md

@@ -31,6 +31,7 @@ Build requirements are:
 
 - meson
 - GTK+3
+- libdrm
 - epoxy
 - wayland-client
 

protocol/meson.build

@@ -21,9 +21,11 @@ wayland_scanner_client = generator(
 
 client_protocols = [
   [wl_protocol_dir, 'unstable/xdg-output/xdg-output-unstable-v1.xml'],
+  [wl_protocol_dir, 'unstable/linux-dmabuf/linux-dmabuf-unstable-v1.xml'],
   [wl_protocol_dir, 'stable/xdg-shell/xdg-shell.xml'],
   ['wlr-output-management-unstable-v1.xml'],
   ['wlr-screencopy-unstable-v1.xml'],
+  ['wlr-export-dmabuf-unstable-v1.xml'],
   ['wlr-layer-shell-unstable-v1.xml']
 ]
 

protocol/wlr-export-dmabuf-unstable-v1.xml

@@ -0,0 +1,203 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<protocol name="wlr_export_dmabuf_unstable_v1">
+  <copyright>
+    Copyright © 2018 Rostislav Pehlivanov
+
+    Permission is hereby granted, free of charge, to any person obtaining a
+    copy of this software and associated documentation files (the "Software"),
+    to deal in the Software without restriction, including without limitation
+    the rights to use, copy, modify, merge, publish, distribute, sublicense,
+    and/or sell copies of the Software, and to permit persons to whom the
+    Software is furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice (including the next
+    paragraph) shall be included in all copies or substantial portions of the
+    Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+    THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+    DEALINGS IN THE SOFTWARE.
+  </copyright>
+
+  <description summary="a protocol for low overhead screen content capturing">
+    An interface to capture surfaces in an efficient way by exporting DMA-BUFs.
+
+    Warning! The protocol described in this file is experimental and
+    backward incompatible changes may be made. Backward compatible changes
+    may be added together with the corresponding interface version bump.
+    Backward incompatible changes are done by bumping the version number in
+    the protocol and interface names and resetting the interface version.
+    Once the protocol is to be declared stable, the 'z' prefix and the
+    version number in the protocol and interface names are removed and the
+    interface version number is reset.
+  </description>
+
+  <interface name="zwlr_export_dmabuf_manager_v1" version="1">
+    <description summary="manager to inform clients and begin capturing">
+      This object is a manager with which to start capturing from sources.
+    </description>
+
+    <request name="capture_output">
+      <description summary="capture a frame from an output">
+        Capture the next frame of a an entire output.
+      </description>
+      <arg name="frame" type="new_id" interface="zwlr_export_dmabuf_frame_v1"/>
+      <arg name="overlay_cursor" type="int"
+           summary="include custom client hardware cursor on top of the frame"/>
+      <arg name="output" type="object" interface="wl_output"/>
+    </request>
+
+    <request name="destroy" type="destructor">
+      <description summary="destroy the manager">
+        All objects created by the manager will still remain valid, until their
+        appropriate destroy request has been called.
+      </description>
+    </request>
+  </interface>
+
+  <interface name="zwlr_export_dmabuf_frame_v1" version="1">
+    <description summary="a DMA-BUF frame">
+      This object represents a single DMA-BUF frame.
+
+      If the capture is successful, the compositor will first send a "frame"
+      event, followed by one or several "object". When the frame is available
+      for readout, the "ready" event is sent.
+
+      If the capture failed, the "cancel" event is sent. This can happen anytime
+      before the "ready" event.
+
+      Once either a "ready" or a "cancel" event is received, the client should
+      destroy the frame. Once an "object" event is received, the client is
+      responsible for closing the associated file descriptor.
+
+      All frames are read-only and may not be written into or altered.
+    </description>
+
+    <enum name="flags">
+      <description summary="frame flags">
+        Special flags that should be respected by the client.
+      </description>
+      <entry name="transient" value="0x1"
+             summary="clients should copy frame before processing"/>
+    </enum>
+
+    <event name="frame">
+      <description summary="a frame description">
+        Main event supplying the client with information about the frame. If the
+        capture didn't fail, this event is always emitted first before any other
+        events.
+
+        This event is followed by a number of "object" as specified by the
+        "num_objects" argument.
+      </description>
+      <arg name="width" type="uint"
+           summary="frame width in pixels"/>
+      <arg name="height" type="uint"
+           summary="frame height in pixels"/>
+      <arg name="offset_x" type="uint"
+           summary="crop offset for the x axis"/>
+      <arg name="offset_y" type="uint"
+           summary="crop offset for the y axis"/>
+      <arg name="buffer_flags" type="uint"
+           summary="flags which indicate properties (invert, interlacing),
+                    has the same values as zwp_linux_buffer_params_v1:flags"/>
+      <arg name="flags" type="uint" enum="flags"
+           summary="indicates special frame features"/>
+      <arg name="format" type="uint"
+           summary="format of the frame (DRM_FORMAT_*)"/>
+      <arg name="mod_high" type="uint"
+           summary="drm format modifier, high"/>
+      <arg name="mod_low" type="uint"
+           summary="drm format modifier, low"/>
+      <arg name="num_objects" type="uint"
+           summary="indicates how many objects (FDs) the frame has (max 4)"/>
+    </event>
+
+    <event name="object">
+      <description summary="an object description">
+        Event which serves to supply the client with the file descriptors
+        containing the data for each object.
+
+        After receiving this event, the client must always close the file
+        descriptor as soon as they're done with it and even if the frame fails.
+      </description>
+      <arg name="index" type="uint"
+           summary="index of the current object"/>
+      <arg name="fd" type="fd"
+           summary="fd of the current object"/>
+      <arg name="size" type="uint"
+           summary="size in bytes for the current object"/>
+      <arg name="offset" type="uint"
+           summary="starting point for the data in the object's fd"/>
+      <arg name="stride" type="uint"
+           summary="line size in bytes"/>
+      <arg name="plane_index" type="uint"
+           summary="index of the the plane the data in the object applies to"/>
+    </event>
+
+    <event name="ready">
+      <description summary="indicates frame is available for reading">
+        This event is sent as soon as the frame is presented, indicating it is
+        available for reading. This event includes the time at which
+        presentation happened at.
+
+        The timestamp is expressed as tv_sec_hi, tv_sec_lo, tv_nsec triples,
+        each component being an unsigned 32-bit value. Whole seconds are in
+        tv_sec which is a 64-bit value combined from tv_sec_hi and tv_sec_lo,
+        and the additional fractional part in tv_nsec as nanoseconds. Hence,
+        for valid timestamps tv_nsec must be in [0, 999999999]. The seconds part
+        may have an arbitrary offset at start.
+
+        After receiving this event, the client should destroy this object.
+      </description>
+      <arg name="tv_sec_hi" type="uint"
+           summary="high 32 bits of the seconds part of the timestamp"/>
+      <arg name="tv_sec_lo" type="uint"
+           summary="low 32 bits of the seconds part of the timestamp"/>
+      <arg name="tv_nsec" type="uint"
+           summary="nanoseconds part of the timestamp"/>
+    </event>
+
+    <enum name="cancel_reason">
+      <description summary="cancel reason">
+        Indicates reason for cancelling the frame.
+      </description>
+      <entry name="temporary" value="0"
+             summary="temporary error, source will produce more frames"/>
+      <entry name="permanent" value="1"
+             summary="fatal error, source will not produce frames"/>
+      <entry name="resizing" value="2"
+             summary="temporary error, source will produce more frames"/>
+    </enum>
+
+    <event name="cancel">
+      <description summary="indicates the frame is no longer valid">
+        If the capture failed or if the frame is no longer valid after the
+        "frame" event has been emitted, this event will be used to inform the
+        client to scrap the frame.
+
+        If the failure is temporary, the client may capture again the same
+        source. If the failure is permanent, any further attempts to capture the
+        same source will fail again.
+
+        After receiving this event, the client should destroy this object.
+      </description>
+      <arg name="reason" type="uint" enum="cancel_reason"
+           summary="indicates a reason for cancelling this frame capture"/>
+    </event>
+
+    <request name="destroy" type="destructor">
+      <description summary="delete this object, used or not">
+        Unreferences the frame. This request must be called as soon as its no
+        longer used.
+
+        It can be called at any time by the client. The client will still have
+        to close any FDs it has been given.
+      </description>
+    </request>
+  </interface>
+</protocol>

src/main.c

@@ -3,11 +3,14 @@
 
 #include <gtk/gtk.h>
 #include <gdk/gdkwayland.h>
+#include <drm_fourcc.h>
 
 #include "wdisplays.h"
 #include "glviewport.h"
 #include "headform.h"
 
+#include "linux-dmabuf-unstable-v1-client-protocol.h"
+
 __attribute__((noreturn)) void wd_fatal_error(int status, const char *message) {
   GtkWindow *parent = gtk_application_get_active_window(GTK_APPLICATION(g_application_get_default()));
   GtkWidget *dialog = gtk_message_dialog_new(parent, GTK_DIALOG_MODAL, GTK_MESSAGE_ERROR, GTK_BUTTONS_OK, "%s", message);
@@ -438,7 +441,11 @@ static void canvas_realize(GtkWidget *widget, gpointer data) {
   }
 
   struct wd_state *state = data;
-  state->gl_data = wd_gl_setup();
+
+  GdkWindow *window = gtk_widget_get_window(widget);
+  GdkDisplay *display = gdk_window_get_display(window);
+  struct wl_display *wl_display = gdk_wayland_display_get_wl_display(display);
+  state->gl_data = wd_gl_setup(wl_display);
 }
 
 static inline bool size_changed(const struct wd_render_head_data *render) {
@@ -524,6 +531,7 @@ static void canvas_render(GtkGLArea *area, GdkGLContext *context, gpointer data)
   uint64_t tick = gdk_frame_clock_get_frame_time(clock);
 
   wd_capture_frame(state);
+  state->render.external_images = state->export_manager != NULL;
 
   struct wd_head *head;
   wl_list_for_each(head, &state->heads, link) {
@@ -534,16 +542,28 @@ static void canvas_render(GtkGLArea *area, GdkGLContext *context, gpointer data)
       frame = wl_container_of(output->frames.prev, frame, link);
     }
     if (render != NULL) {
-      if (state->capture && frame != NULL && frame->pixels != NULL) {
+      if (state->capture && frame != NULL && frame->ready) {
         if (frame->tick > render->updated_at) {
-          render->tex_stride = frame->stride;
           render->tex_width = frame->width;
           render->tex_height = frame->height;
+          if (state->render.external_images) {
+            render->pixels = NULL;
+            render->image = wd_gl_create_dmabuf_texture(state->gl_data, frame);
+            render->has_alpha = TRUE;
+            render->swap_rgb = TRUE;
+          } else {
             render->pixels = frame->pixels;
+            render->image = NULL;
+            render->tex_stride = frame->strides[0];
+            render->swap_rgb = frame->format == WL_SHM_FORMAT_ABGR8888
+              || frame->format == WL_SHM_FORMAT_XBGR8888;
+            render->has_alpha = frame->format == WL_SHM_FORMAT_ARGB8888
+              || frame->format == WL_SHM_FORMAT_ABGR8888;
+          }
+          render->y_invert = frame->flags &
+            ZWP_LINUX_BUFFER_PARAMS_V1_FLAGS_Y_INVERT;
           render->preview = TRUE;
           render->updated_at = tick;
-          render->y_invert = frame->y_invert;
-          render->swap_rgb = frame->swap_rgb;
         }
         if (render->preview) {
           render->active.rotation = render->queued.rotation;
@@ -560,10 +580,12 @@ static void canvas_render(GtkGLArea *area, GdkGLContext *context, gpointer data)
         head->surface = draw_head(pango, &state->render, head->name,
             render->tex_width, render->tex_height);
         render->pixels = cairo_image_surface_get_data(head->surface);
+        render->image = NULL;
         render->tex_stride = cairo_image_surface_get_stride(head->surface);
         render->updated_at = tick;
         render->active.rotation = 0;
         render->active.x_invert = FALSE;
+        render->has_alpha = FALSE;
         render->y_invert = FALSE;
         render->swap_rgb = FALSE;
       }
@@ -1054,7 +1076,7 @@ static void activate(GtkApplication* app, gpointer user_data) {
   if (state->xdg_output_manager == NULL) {
     wd_fatal_error(1, "Compositor doesn't support xdg-output-unstable-v1");
   }
-  if (state->copy_manager == NULL) {
+  if (state->copy_manager == NULL && state->export_manager == NULL) {
     state->capture = FALSE;
     g_simple_action_set_state(capture_action, g_variant_new_boolean(state->capture));
     g_simple_action_set_enabled(capture_action, FALSE);

src/meson.build

@@ -8,6 +8,7 @@ gdk = dependency('gdk-3.0', version: '>= 3.24')
 gtk = dependency('gtk+-3.0', version: '>= 3.24')
 assert(gdk.get_pkgconfig_variable('targets').split().contains('wayland'), 'Wayland GDK backend not present')
 epoxy = dependency('epoxy')
+libdrm = dependency('libdrm')
 
 configure_file(input: 'config.h.in', output: 'config.h', configuration: conf)
 
@@ -28,6 +29,7 @@ executable(
     wayland_client,
     client_protos,
     epoxy,
+    libdrm,
     gtk
   ],
   install: true

src/outputs.c

@@ -25,6 +25,8 @@
 
 #include "wlr-output-management-unstable-v1-client-protocol.h"
 #include "xdg-output-unstable-v1-client-protocol.h"
+#include "linux-dmabuf-unstable-v1-client-protocol.h"
+#include "wlr-export-dmabuf-unstable-v1-client-protocol.h"
 #include "wlr-screencopy-unstable-v1-client-protocol.h"
 #include "wlr-layer-shell-unstable-v1-client-protocol.h"
 
@@ -143,15 +145,18 @@ void wd_apply_state(struct wd_state *state, struct wl_list *new_outputs,
 
 static void wd_frame_destroy(struct wd_frame *frame) {
   if (frame->pixels != NULL)
-    munmap(frame->pixels, frame->height * frame->stride);
+    munmap(frame->pixels, frame->height * frame->strides[0]);
   if (frame->buffer != NULL)
     wl_buffer_destroy(frame->buffer);
   if (frame->pool != NULL)
     wl_shm_pool_destroy(frame->pool);
-  if (frame->capture_fd != -1)
-    close(frame->capture_fd);
-  if (frame->wlr_frame != NULL)
-    zwlr_screencopy_frame_v1_destroy(frame->wlr_frame);
+  for (int i = 0; i < frame->n_planes; i++)
+    if (frame->fds[i])
+      close(frame->fds[i]);
+  if (frame->copy_frame != NULL)
+    zwlr_screencopy_frame_v1_destroy(frame->copy_frame);
+  if (frame->export_frame != NULL)
+    zwlr_export_dmabuf_frame_v1_destroy(frame->export_frame);
 
   wl_list_remove(&frame->link);
   free(frame);
@@ -189,6 +194,112 @@ static int create_shm_file(size_t size, const char *fmt, ...) {
   return fd;
 }
 
+static void make_frame_current(struct wd_frame *frame,
+    uint32_t tv_sec_hi, uint32_t tv_sec_lo, uint32_t tv_nsec) {
+  uint64_t tv_sec = (uint64_t) tv_sec_hi << 32 | tv_sec_lo;
+  frame->tick = (tv_sec * 1000000) + (tv_nsec / 1000);
+
+  struct wd_frame *frame_iter, *frame_tmp;
+  wl_list_for_each_safe(frame_iter, frame_tmp, &frame->output->frames, link) {
+    if (frame != frame_iter) {
+      wd_frame_destroy(frame_iter);
+    }
+  }
+}
+
+#define WD_FRAME_COPY 0x100
+
+static void export_frame(void *data,
+    struct zwlr_export_dmabuf_frame_v1 *wlr_frame,
+    uint32_t width, uint32_t height, uint32_t offset_x, uint32_t offset_y,
+    uint32_t buffer_flags, uint32_t flags, uint32_t format,
+    uint32_t mod_high, uint32_t mod_low, uint32_t num_objects) {
+  struct wd_frame *frame = data;
+  frame->width = width;
+  frame->height = height;
+  frame->format = format;
+  frame->flags = buffer_flags;
+/*
+  if (flags & ZWLR_EXPORT_DMABUF_FRAME_V1_FLAGS_TRANSIENT) {
+    frame->flags |= WD_FRAME_COPY;
+  }
+*/
+  frame->modifier = ((uint64_t) mod_high << 32) | mod_low;
+  frame->n_planes = num_objects;
+}
+
+static void export_object(void *data,
+    struct zwlr_export_dmabuf_frame_v1 *wlr_frame,
+    uint32_t index, int32_t fd, uint32_t size, uint32_t offset,
+    uint32_t stride, uint32_t plane_index) {
+  struct wd_frame *frame = data;
+
+  if (frame->flags & WD_FRAME_COPY) {
+    void *src = NULL;
+    void *dest = NULL;
+    int wfd = create_shm_file(size, "/wd-%s", frame->output->name);
+    if (wfd == -1) {
+      goto done;
+    }
+    src = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, offset);
+    if (src == MAP_FAILED) {
+      fprintf(stderr, "mmap: %d: %s\n", fd, strerror(errno));
+      close(wfd);
+      wfd = -1;
+      goto done;
+    }
+    dest = mmap(NULL, size - offset, PROT_READ | PROT_WRITE,
+        MAP_PRIVATE, wfd, 0);
+    if (dest == MAP_FAILED) {
+      fprintf(stderr, "mmap: %d: %s\n", wfd, strerror(errno));
+      close(wfd);
+      wfd = -1;
+      goto done;
+    }
+    memcpy(dest, src, size - offset);
+done:
+    if (src)
+      munmap(src, size);
+    if (dest)
+      munmap(dest, size - offset);
+    close(fd);
+    frame->fds[plane_index] = wfd;
+  } else {
+    frame->fds[plane_index] = fd;
+    frame->offsets[plane_index] = offset;
+  }
+  frame->strides[plane_index] = stride;
+}
+
+static void export_ready(void *data,
+    struct zwlr_export_dmabuf_frame_v1 *wlr_frame,
+    uint32_t tv_sec_hi, uint32_t tv_sec_lo, uint32_t tv_nsec) {
+  struct wd_frame *frame = data;
+
+  make_frame_current(frame, tv_sec_hi, tv_sec_lo, tv_nsec);
+
+  if (frame->flags & WD_FRAME_COPY) {
+    frame->flags ^= WD_FRAME_COPY;
+    zwlr_export_dmabuf_frame_v1_destroy(frame->export_frame);
+    frame->export_frame = NULL;
+  }
+  frame->ready = true;
+}
+
+static void export_cancel(void *data,
+    struct zwlr_export_dmabuf_frame_v1 *wlr_frame,
+    uint32_t reason) {
+  struct wd_frame *frame = data;
+  wd_frame_destroy(frame);
+}
+
+static struct zwlr_export_dmabuf_frame_v1_listener export_listener = {
+  .frame = export_frame,
+  .object = export_object,
+  .ready = export_ready,
+  .cancel = export_cancel
+};
+
 static void capture_buffer(void *data,
     struct zwlr_screencopy_frame_v1 *copy_frame,
     uint32_t format, uint32_t width, uint32_t height, uint32_t stride) {
@@ -199,22 +310,23 @@ static void capture_buffer(void *data,
     goto err;
   }
 
+  frame->n_planes = 1;
   size_t size = stride * height;
-  frame->capture_fd = create_shm_file(size, "/wd-%s", frame->output->name);
-  if (frame->capture_fd == -1) {
+  frame->fds[0] = create_shm_file(size, "/wd-%s", frame->output->name);
+  if (frame->fds[0] == -1) {
     goto err;
   }
 
   frame->pool = wl_shm_create_pool(frame->output->state->shm,
-      frame->capture_fd, size);
+      frame->fds[0], size);
   frame->buffer = wl_shm_pool_create_buffer(frame->pool, 0,
       width, height, stride, format);
   zwlr_screencopy_frame_v1_copy(copy_frame, frame->buffer);
-  frame->stride = stride;
+  frame->offsets[0] = 0;
+  frame->strides[0] = stride;
   frame->width = width;
   frame->height = height;
-  frame->swap_rgb = format == WL_SHM_FORMAT_ABGR8888
-    || format == WL_SHM_FORMAT_XBGR8888;
+  frame->format = format;
 
   return;
 err:
@@ -225,7 +337,9 @@ static void capture_flags(void *data,
     struct zwlr_screencopy_frame_v1 *wlr_frame,
     uint32_t flags) {
   struct wd_frame *frame = data;
-  frame->y_invert = !!(flags & ZWLR_SCREENCOPY_FRAME_V1_FLAGS_Y_INVERT);
+  if (flags & ZWLR_SCREENCOPY_FRAME_V1_FLAGS_Y_INVERT) {
+    frame->flags |= ZWP_LINUX_BUFFER_PARAMS_V1_FLAGS_Y_INVERT;
+  }
 }
 
 static void capture_ready(void *data,
@@ -233,27 +347,20 @@ static void capture_ready(void *data,
     uint32_t tv_sec_hi, uint32_t tv_sec_lo, uint32_t tv_nsec) {
   struct wd_frame *frame = data;
 
-  frame->pixels = mmap(NULL, frame->stride * frame->height,
-      PROT_READ, MAP_SHARED, frame->capture_fd, 0);
+  frame->pixels = mmap(NULL, frame->strides[0] * frame->height,
+      PROT_READ, MAP_SHARED, frame->fds[0], 0);
   if (frame->pixels == MAP_FAILED) {
     frame->pixels = NULL;
-    fprintf(stderr, "mmap: %d: %s\n", frame->capture_fd, strerror(errno));
+    fprintf(stderr, "mmap: %d: %s\n", frame->fds[0], strerror(errno));
     wd_frame_destroy(frame);
     return;
-  } else {
-    uint64_t tv_sec = (uint64_t) tv_sec_hi << 32 | tv_sec_lo;
-    frame->tick = (tv_sec * 1000000) + (tv_nsec / 1000);
   }
   
-  zwlr_screencopy_frame_v1_destroy(frame->wlr_frame);
-  frame->wlr_frame = NULL;
+  make_frame_current(frame, tv_sec_hi, tv_sec_lo, tv_nsec);
 
-  struct wd_frame *frame_iter, *frame_tmp;
-  wl_list_for_each_safe(frame_iter, frame_tmp, &frame->output->frames, link) {
-    if (frame != frame_iter) {
-      wd_frame_destroy(frame_iter);
-    }
-  }
+  zwlr_screencopy_frame_v1_destroy(frame->copy_frame);
+  frame->copy_frame = NULL;
+  frame->ready = true;
 }
 
 static void capture_failed(void *data,
@@ -274,7 +381,7 @@ static bool has_pending_captures(struct wd_state *state) {
   wl_list_for_each(output, &state->outputs, link) {
     struct wd_frame *frame;
     wl_list_for_each(frame, &output->frames, link) {
-      if (frame->pixels == NULL) {
+      if (!frame->ready) {
         return true;
       }
     }
@@ -283,8 +390,8 @@ static bool has_pending_captures(struct wd_state *state) {
 }
 
 void wd_capture_frame(struct wd_state *state) {
-  if (state->copy_manager == NULL || has_pending_captures(state)
-      || !state->capture) {
+  if ((state->export_manager == NULL && state->copy_manager == NULL)
+       || has_pending_captures(state) || !state->capture) {
     return;
   }
 
@@ -292,12 +399,21 @@ void wd_capture_frame(struct wd_state *state) {
   wl_list_for_each(output, &state->outputs, link) {
     struct wd_frame *frame = calloc(1, sizeof(*frame));
     frame->output = output;
-    frame->capture_fd = -1;
-    frame->wlr_frame =
+    for (int i = 0; i < WD_MAX_PLANES; i++)
+      frame->fds[i] = -1;
+    if (state->export_manager) {
+      frame->export_frame =
+        zwlr_export_dmabuf_manager_v1_capture_output(state->export_manager, 1,
+          output->wl_output);
+      zwlr_export_dmabuf_frame_v1_add_listener(frame->export_frame,
+          &export_listener, frame);
+    } else if (state->copy_manager) {
+      frame->copy_frame =
         zwlr_screencopy_manager_v1_capture_output(state->copy_manager, 1,
           output->wl_output);
-    zwlr_screencopy_frame_v1_add_listener(frame->wlr_frame, &capture_listener,
-        frame);
+      zwlr_screencopy_frame_v1_add_listener(frame->copy_frame,
+          &capture_listener, frame);
+    }
     wl_list_insert(&output->frames, &frame->link);
   }
 }
@@ -540,6 +656,9 @@ static void registry_handle_global(void *data, struct wl_registry *registry,
   } else if (strcmp(interface, zxdg_output_manager_v1_interface.name) == 0) {
     state->xdg_output_manager = wl_registry_bind(registry, name,
         &zxdg_output_manager_v1_interface, version);
+  } else if(strcmp(interface, zwlr_export_dmabuf_manager_v1_interface.name) == 0) {
+    state->export_manager = wl_registry_bind(registry, name,
+        &zwlr_export_dmabuf_manager_v1_interface, version);
   } else if(strcmp(interface, zwlr_screencopy_manager_v1_interface.name) == 0) {
     state->copy_manager = wl_registry_bind(registry, name,
         &zwlr_screencopy_manager_v1_interface, version);
@@ -689,6 +808,9 @@ void wd_state_destroy(struct wd_state *state) {
   if (state->layer_shell != NULL) {
     zwlr_layer_shell_v1_destroy(state->layer_shell);
   }
+  if (state->export_manager != NULL) {
+    zwlr_export_dmabuf_manager_v1_destroy(state->export_manager);
+  }
   if (state->copy_manager != NULL) {
     zwlr_screencopy_manager_v1_destroy(state->copy_manager);
   }

src/render.c

@@ -1,13 +1,24 @@
 /* SPDX-FileCopyrightText: 2020 Jason Francis <jason@cycles.network>
  * SPDX-License-Identifier: GPL-3.0-or-later */
+/* SPDX-FileCopyrightText: 2018 Simon Ser
+ * SPDX-FileCopyrightText: 2018 Guido Günther
+ * SPDX-License-Identifier: MIT */
+/* Parts of this file are taken from swaywm/wlroots:
+ * https://github.com/swaywm/wlroots/blob/e97c2c3639119831ced4f6b9f704b096c2075973/render/egl.c
+ */
 
 #include "wdisplays.h"
 
+#define WL_EGL_PLATFORM 1
+
+#include <assert.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <math.h>
-#include <epoxy/gl.h>
 #include <wayland-util.h>
+#include <epoxy/gl.h>
+#include <epoxy/egl.h>
+#include <drm_fourcc.h>
 
 #define BT_UV_VERT_SIZE (2 + 2)
 #define BT_UV_QUAD_SIZE (6 * BT_UV_VERT_SIZE)
@@ -29,22 +40,25 @@ enum gl_buffers {
   NUM_BUFFERS
 };
 
+struct wd_gl_texture_program {
+  GLuint id;
+  GLuint position_attribute;
+  GLuint uv_attribute;
+  GLuint screen_size_uniform;
+  GLuint texture_uniform;
+  GLuint color_transform_uniform;
+  GLuint color_add_uniform;
+};
+
 struct wd_gl_data {
+  EGLDisplay display;
+
   GLuint color_program;
-  GLuint color_vertex_shader;
-  GLuint color_fragment_shader;
   GLuint color_position_attribute;
   GLuint color_color_attribute;
   GLuint color_screen_size_uniform;
 
-  GLuint texture_program;
-  GLuint texture_vertex_shader;
-  GLuint texture_fragment_shader;
-  GLuint texture_position_attribute;
-  GLuint texture_uv_attribute;
-  GLuint texture_screen_size_uniform;
-  GLuint texture_texture_uniform;
-  GLuint texture_color_transform_uniform;
+  struct wd_gl_texture_program rgb;
 
   GLuint buffers[NUM_BUFFERS];
 
@@ -90,8 +104,9 @@ precision mediump float;\n\
 varying vec2 uv_out;\n\
 uniform sampler2D texture;\n\
 uniform mat4 color_transform;\n\
+uniform vec4 color_add;\n\
 void main(void) {\n\
-  gl_FragColor = texture2D(texture, uv_out) * color_transform;\n\
+  gl_FragColor = texture2D(texture, uv_out) * color_transform + color_add;\n\
 }";
 
 static GLuint gl_make_shader(GLenum type, const char *src) {
@@ -142,18 +157,62 @@ static void gl_link_and_validate(GLint program) {
   }
 }
 
-struct wd_gl_data *wd_gl_setup(void) {
+static void setup_texture_program(struct wd_gl_texture_program *prog,
+  const char *fragment_src) {
+  prog->id = glCreateProgram();
+
+  GLuint vertex_shader = gl_make_shader(GL_VERTEX_SHADER,
+      texture_vertex_shader_src);
+  glAttachShader(prog->id, vertex_shader);
+  GLuint fragment_shader = gl_make_shader(GL_FRAGMENT_SHADER, fragment_src);
+  glAttachShader(prog->id, fragment_shader);
+  gl_link_and_validate(prog->id);
+
+  glDeleteShader(fragment_shader);
+  glDeleteShader(vertex_shader);
+
+  prog->position_attribute = glGetAttribLocation(prog->id, "position");
+  prog->uv_attribute = glGetAttribLocation(prog->id, "uv");
+  prog->screen_size_uniform = glGetUniformLocation(prog->id, "screen_size");
+  prog->texture_uniform = glGetUniformLocation(prog->id, "texture");
+  prog->color_transform_uniform = glGetUniformLocation(prog->id,
+      "color_transform");
+  prog->color_add_uniform = glGetUniformLocation(prog->id, "color_add");
+}
+
+#define assert_ext(_name, _expr) do { \
+  static bool _tested_##_name = false; \
+  if (!_tested_##_name) { \
+    _tested_##_name = true; \
+    if (!(_expr)) \
+      wd_fatal_error(1, "Extension " #_name " not found\n"); \
+  } \
+} while (0)
+
+#define assert_gl_ext(_name) \
+  assert_ext(_name, epoxy_has_gl_extension(#_name))
+
+#define assert_egl_ext(_res, _name) \
+  assert_ext(_name, epoxy_has_egl_extension((_res)->display, #_name))
+   
+struct wd_gl_data *wd_gl_setup(struct wl_display *display) {
   struct wd_gl_data *res = calloc(1, sizeof(struct wd_gl_data));
+  res->display = eglGetDisplay(display);
   res->color_program = glCreateProgram();
 
-  res->color_vertex_shader = gl_make_shader(GL_VERTEX_SHADER,
+  GLuint vertex_shader = gl_make_shader(GL_VERTEX_SHADER,
       color_vertex_shader_src);
-  glAttachShader(res->color_program, res->color_vertex_shader);
-  res->color_fragment_shader = gl_make_shader(GL_FRAGMENT_SHADER,
+  glAttachShader(res->color_program, vertex_shader);
+  GLuint fragment_shader = gl_make_shader(GL_FRAGMENT_SHADER,
       color_fragment_shader_src);
-  glAttachShader(res->color_program, res->color_fragment_shader);
+  glAttachShader(res->color_program, fragment_shader);
   gl_link_and_validate(res->color_program);
 
+  glDeleteShader(fragment_shader);
+  glDeleteShader(vertex_shader);
+
+  setup_texture_program(&res->rgb, texture_fragment_shader_src);
+
   res->color_position_attribute = glGetAttribLocation(res->color_program,
       "position");
   res->color_color_attribute = glGetAttribLocation(res->color_program,
@@ -161,27 +220,6 @@ struct wd_gl_data *wd_gl_setup(void) {
   res->color_screen_size_uniform = glGetUniformLocation(res->color_program,
       "screen_size");
 
-  res->texture_program = glCreateProgram();
-
-  res->texture_vertex_shader = gl_make_shader(GL_VERTEX_SHADER,
-      texture_vertex_shader_src);
-  glAttachShader(res->texture_program, res->texture_vertex_shader);
-  res->texture_fragment_shader = gl_make_shader(GL_FRAGMENT_SHADER,
-      texture_fragment_shader_src);
-  glAttachShader(res->texture_program, res->texture_fragment_shader);
-  gl_link_and_validate(res->texture_program);
-
-  res->texture_position_attribute = glGetAttribLocation(res->texture_program,
-      "position");
-  res->texture_uv_attribute = glGetAttribLocation(res->texture_program,
-      "uv");
-  res->texture_screen_size_uniform = glGetUniformLocation(res->texture_program,
-      "screen_size");
-  res->texture_texture_uniform = glGetUniformLocation(res->texture_program,
-      "texture");
-  res->texture_color_transform_uniform = glGetUniformLocation(
-      res->texture_program, "color_transform");
-
   glGenBuffers(NUM_BUFFERS, res->buffers);
   glBindBuffer(GL_ARRAY_BUFFER, res->buffers[TEXTURE_BUFFER]);
   glBufferData(GL_ARRAY_BUFFER, BT_UV_MAX * sizeof(float),
@@ -198,6 +236,83 @@ struct wd_gl_data *wd_gl_setup(void) {
   return res;
 }
 
+EGLImageKHR wd_gl_create_dmabuf_texture(struct wd_gl_data *res,
+    struct wd_frame *frame) {
+  assert(!frame->pixels);
+  assert_egl_ext(res, EGL_KHR_image_base);
+  assert_egl_ext(res, EGL_EXT_image_dma_buf_import);
+
+  bool has_modifier = frame->modifier != DRM_FORMAT_MOD_INVALID
+    && frame->modifier != DRM_FORMAT_MOD_LINEAR;
+
+  if (has_modifier) {
+    assert_egl_ext(res, EGL_EXT_image_dma_buf_import_modifiers);
+  }
+
+  unsigned int atti = 0;
+  EGLint attribs[50];
+  attribs[atti++] = EGL_WIDTH;
+  attribs[atti++] = frame->width;
+  attribs[atti++] = EGL_HEIGHT;
+  attribs[atti++] = frame->height;
+  attribs[atti++] = EGL_LINUX_DRM_FOURCC_EXT;
+  attribs[atti++] = frame->format;
+
+  struct {
+    EGLint fd;
+    EGLint offset;
+    EGLint pitch;
+    EGLint mod_lo;
+    EGLint mod_hi;
+  } attr_names[WD_MAX_PLANES] = {
+    {
+      EGL_DMA_BUF_PLANE0_FD_EXT,
+      EGL_DMA_BUF_PLANE0_OFFSET_EXT,
+      EGL_DMA_BUF_PLANE0_PITCH_EXT,
+      EGL_DMA_BUF_PLANE0_MODIFIER_LO_EXT,
+      EGL_DMA_BUF_PLANE0_MODIFIER_HI_EXT
+    }, {
+      EGL_DMA_BUF_PLANE1_FD_EXT,
+      EGL_DMA_BUF_PLANE1_OFFSET_EXT,
+      EGL_DMA_BUF_PLANE1_PITCH_EXT,
+      EGL_DMA_BUF_PLANE1_MODIFIER_LO_EXT,
+      EGL_DMA_BUF_PLANE1_MODIFIER_HI_EXT
+    }, {
+      EGL_DMA_BUF_PLANE2_FD_EXT,
+      EGL_DMA_BUF_PLANE2_OFFSET_EXT,
+      EGL_DMA_BUF_PLANE2_PITCH_EXT,
+      EGL_DMA_BUF_PLANE2_MODIFIER_LO_EXT,
+      EGL_DMA_BUF_PLANE2_MODIFIER_HI_EXT
+    }, {
+      EGL_DMA_BUF_PLANE3_FD_EXT,
+      EGL_DMA_BUF_PLANE3_OFFSET_EXT,
+      EGL_DMA_BUF_PLANE3_PITCH_EXT,
+      EGL_DMA_BUF_PLANE3_MODIFIER_LO_EXT,
+      EGL_DMA_BUF_PLANE3_MODIFIER_HI_EXT
+    }
+  };
+
+  for (int i=0; i < frame->n_planes; i++) {
+    attribs[atti++] = attr_names[i].fd;
+    attribs[atti++] = frame->fds[i];
+    attribs[atti++] = attr_names[i].offset;
+    attribs[atti++] = frame->offsets[i];
+    attribs[atti++] = attr_names[i].pitch;
+    attribs[atti++] = frame->strides[i];
+    if (has_modifier) {
+      attribs[atti++] = attr_names[i].mod_lo;
+      attribs[atti++] = frame->modifier & 0xFFFFFFFF;
+      attribs[atti++] = attr_names[i].mod_hi;
+      attribs[atti++] = frame->modifier >> 32;
+    }
+  }
+  attribs[atti++] = EGL_NONE;
+  assert(atti < sizeof(attribs)/sizeof(attribs[0]));
+
+  return eglCreateImageKHR(res->display, EGL_NO_CONTEXT,
+      EGL_LINUX_DMA_BUF_EXT, NULL, attribs);
+}
+
 static const GLfloat TRANSFORM_RGB[16] = {
   1, 0, 0, 0,
   0, 1, 0, 0,
@@ -320,34 +435,42 @@ void wd_gl_render(struct wd_gl_data *res, struct wd_render_data *info,
   float screen_size[2] = { info->viewport_width, info->viewport_height };
 
   if (tri_verts > 0) {
-    glUseProgram(res->texture_program);
+    glUseProgram(res->rgb.id);
     glBindBuffer(GL_ARRAY_BUFFER, res->buffers[TEXTURE_BUFFER]);
     glBufferSubData(GL_ARRAY_BUFFER, 0,
         tri_verts * BT_UV_VERT_SIZE * sizeof(float), res->verts);
-    glEnableVertexAttribArray(res->texture_position_attribute);
-    glEnableVertexAttribArray(res->texture_uv_attribute);
-    glVertexAttribPointer(res->texture_position_attribute,
+    glEnableVertexAttribArray(res->rgb.position_attribute);
+    glEnableVertexAttribArray(res->rgb.uv_attribute);
+    glVertexAttribPointer(res->rgb.position_attribute,
         2, GL_FLOAT, GL_FALSE,
         BT_UV_VERT_SIZE * sizeof(float), (void *) (0 * sizeof(float)));
-    glVertexAttribPointer(res->texture_uv_attribute, 2, GL_FLOAT, GL_FALSE,
+    glVertexAttribPointer(res->rgb.uv_attribute, 2, GL_FLOAT, GL_FALSE,
         BT_UV_VERT_SIZE * sizeof(float), (void *) (2 * sizeof(float)));
-    glUniform2fv(res->texture_screen_size_uniform, 1, screen_size);
-    glUniform1i(res->texture_texture_uniform, 0);
+    glUniform2fv(res->rgb.screen_size_uniform, 1, screen_size);
+    glUniform1i(res->rgb.texture_uniform, 0);
     glActiveTexture(GL_TEXTURE0);
 
     i = 0;
     wl_list_for_each_reverse(head, &info->heads, link) {
       glBindTexture(GL_TEXTURE_2D, res->textures[i]);
       if (head->updated_at == tick) {
+        if (head->image) {
+          assert_gl_ext(GL_OES_EGL_image);
+          glEGLImageTargetTexture2DOES(GL_TEXTURE_2D, head->image);
+        } else if (head->pixels) {
+          assert_gl_ext(GL_EXT_unpack_subimage);
           glPixelStorei(GL_UNPACK_ROW_LENGTH_EXT, head->tex_stride / 4);
           glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA,
               head->tex_width, head->tex_height,
               0, GL_RGBA, GL_UNSIGNED_BYTE, head->pixels);
           glPixelStorei(GL_UNPACK_ROW_LENGTH_EXT, 0);
+        }
         glGenerateMipmap(GL_TEXTURE_2D);
       }
-      glUniformMatrix4fv(res->texture_color_transform_uniform, 1, GL_FALSE,
+      glUniformMatrix4fv(res->rgb.color_transform_uniform, 1, GL_FALSE,
         head->swap_rgb ? TRANSFORM_RGB : TRANSFORM_BGR);
+      float color_add[4] = { 0.f, 0.f, 0.f, head->has_alpha ? 0.f : 1.f };
+      glUniform4fv(res->rgb.color_add_uniform, 1, color_add);
       glDrawArrays(GL_TRIANGLES, i * 6, 6);
       i++;
       if (i >= HEADS_MAX)
@@ -514,13 +637,9 @@ void wd_gl_render(struct wd_gl_data *res, struct wd_render_data *info,
 
 void wd_gl_cleanup(struct wd_gl_data *res) {
   glDeleteBuffers(NUM_BUFFERS, res->buffers);
-  glDeleteShader(res->texture_fragment_shader);
-  glDeleteShader(res->texture_vertex_shader);
-  glDeleteProgram(res->texture_program);
-
-  glDeleteShader(res->color_fragment_shader);
-  glDeleteShader(res->color_vertex_shader);
   glDeleteProgram(res->color_program);
 
+  glDeleteProgram(res->rgb.id);
+
   free(res);
 }

src/wdisplays.h

@@ -27,6 +27,8 @@ struct zxdg_output_manager_v1;
 struct zwlr_output_mode_v1;
 struct zwlr_output_head_v1;
 struct zwlr_output_manager_v1;
+struct zwlr_export_dmabuf_manager_v1;
+struct zwlr_export_dmabuf_frame_v1;
 struct zwlr_screencopy_manager_v1;
 struct zwlr_screencopy_frame_v1;
 struct zwlr_layer_shell_v1;
@@ -41,6 +43,8 @@ typedef struct _GdkCursor GdkCursor;
 struct _cairo_surface;
 typedef struct _cairo_surface cairo_surface_t;
 
+typedef void *EGLImageKHR;
+
 struct wd_output {
   struct wd_state *state;
   struct zxdg_output_v1 *xdg_output;
@@ -53,21 +57,30 @@ struct wd_output {
   struct zwlr_layer_surface_v1 *overlay_layer_surface;
 };
 
+#define WD_MAX_PLANES 4
+
 struct wd_frame {
   struct wd_output *output;
-  struct zwlr_screencopy_frame_v1 *wlr_frame;
+  struct zwlr_export_dmabuf_frame_v1 *export_frame;
+  struct zwlr_screencopy_frame_v1 *copy_frame;
 
   struct wl_list link;
-  int capture_fd;
-  unsigned stride;
+
   unsigned width;
   unsigned height;
+  uint64_t tick;
+
+  uint32_t format;
+  uint32_t flags;
+  uint64_t modifier;
+  uint32_t n_planes;
+  int fds[WD_MAX_PLANES];
+  uint32_t offsets[WD_MAX_PLANES];
+  uint32_t strides[WD_MAX_PLANES];
   struct wl_shm_pool *pool;
   struct wl_buffer *buffer;
   uint8_t *pixels;
-  uint64_t tick;
-  bool y_invert;
-  bool swap_rgb;
+  bool ready;
 };
 
 struct wd_head_config {
@@ -141,15 +154,17 @@ struct wd_render_head_data {
   struct wd_render_head_flags active;
 
   uint8_t *pixels;
+  EGLImageKHR image;
   unsigned tex_stride;
   unsigned tex_width;
   unsigned tex_height;
 
-  bool preview;
-  bool y_invert;
-  bool swap_rgb;
-  bool hovered;
-  bool clicked;
+  uint32_t preview : 1,
+           y_invert : 1,
+           swap_rgb : 1,
+           has_alpha : 1,
+           hovered : 1,
+           clicked : 1;
 };
 
 struct wd_render_data {
@@ -166,6 +181,7 @@ struct wd_render_data {
   int x_origin;
   int y_origin;
   uint64_t updated_at;
+  bool external_images;
 
   struct wl_list heads;
 };
@@ -178,6 +194,7 @@ struct wd_point {
 struct wd_state {
   struct zxdg_output_manager_v1 *xdg_output_manager;
   struct zwlr_output_manager_v1 *output_manager;
+  struct zwlr_export_dmabuf_manager_v1 *export_manager;
   struct zwlr_screencopy_manager_v1 *copy_manager;
   struct zwlr_layer_shell_v1 *layer_shell;
   struct wl_shm *shm;
@@ -311,8 +328,14 @@ void wd_ui_show_error(struct wd_state *state, const char *message);
 /*
  * Compiles the GL shaders.
  */
-struct wd_gl_data *wd_gl_setup(void);
+struct wd_gl_data *wd_gl_setup(struct wl_display *display);
 
+/*
+ * Creates an EGLImage from a given output frame. The frame must have a dmabuf
+ * received from a wlr_export_dmabuf_frame.
+ */
+EGLImageKHR wd_gl_create_dmabuf_texture(struct wd_gl_data *res,
+    struct wd_frame *frame);
 /*
  * Renders the GL scene.
  */