Make supervisor_export_image use FBO instead of screen framebuffer. (c…

…yberbotics#6622)

* Make supervisor_export_image use FBO instead of screen framebuffer.

This makes the supervisor_export_image test pass under Wayland and has the added benefit of making that test (and the billboard test) work with "--no-rendering --minimize". As a result those tests are moved into the api group and the with_rendering group is removed.

* Add changelog entry.

docs/reference/changelog-r2024.md

@@ -22,3 +22,4 @@ Released on December **th, 2023.
     - Fixed the bug that when the language is Python, getTargets() cannot correctly obtain the multi-target data detected by the radar ([#6606](https://github.com/cyberbotics/webots/pull/6606))
     - Fixed incomplete loading while minimized under some windowing systems ([#6617](https://github.com/cyberbotics/webots/pull/6617)).
     - Fixed unitialized sliding friction when using asymmetric rolling friction ([#6618](https://github.com/cyberbotics/webots/pull/6618)).
+    - Made `supervisor_export_image` work even if using the `--minimize --no-rendering` options ([#6622](https://github.com/cyberbotics/webots/pull/6622)).

include/wren/scene.h

@@ -68,8 +68,7 @@ void wr_scene_enable_depth_reset(WrScene *scene, bool enable);
 void wr_scene_add_frame_listener(WrScene *scene, void (*listener)());
 void wr_scene_remove_frame_listener(WrScene *scene, void (*listener)());
 
-void wr_scene_get_main_buffer(WrScene *scene, int width, int height, unsigned int format, unsigned int data_type,
-                              unsigned int buffer_type, void *buffer);
+void wr_scene_get_main_buffer(int width, int height, unsigned int format, unsigned int data_type, void *buffer);
 
 void wr_scene_init_frame_capture(WrScene *scene, int pixel_buffer_count, unsigned int *pixel_buffer_ids, int frame_size);
 void wr_scene_bind_pixel_buffer(WrScene *scene, int buffer);

src/webots/gui/WbView3D.cpp

@@ -332,7 +332,7 @@ void WbView3D::refresh() {
   const WbSimulationState *const sim = WbSimulationState::instance();
   mPhysicsRefresh = true;
   if (mScreenshotRequested)
-    renderNow();
+    renderNow(true, true);
   else if (sim->isPaused())
     renderLater();
   else if (WbVideoRecorder::instance()->isRecording()) {

src/webots/gui/WbWrenWindow.cpp

@@ -446,15 +446,5 @@ void WbWrenWindow::feedMultimediaStreamer() {
 }
 
 void WbWrenWindow::readPixels(int width, int height, unsigned int format, void *buffer) {
-#ifdef __linux__
-  if (WbSysInfo::isVirtualMachine()) {
-    // Reading the front buffer is not supported by all OpenGL implementations (especially on Linux running in a VM).
-    // In that case, to read the front buffer, we need to swap the buffers, read the back buffer and swap the buffers again.
-    // However, doing this may cause flickering on platforms where reading the front buffer is supported (including macOS).
-    WbWrenOpenGlContext::instance()->swapBuffers(this);
-    wr_scene_get_main_buffer(wr_scene_get_instance(), width, height, format, GL_UNSIGNED_BYTE, GL_BACK, buffer);
-    WbWrenOpenGlContext::instance()->swapBuffers(this);
-  } else
-#endif
-    wr_scene_get_main_buffer(wr_scene_get_instance(), width, height, format, GL_UNSIGNED_BYTE, GL_FRONT, buffer);
+  wr_scene_get_main_buffer(width, height, format, GL_UNSIGNED_BYTE, buffer);
 }

src/wren/Scene.cpp

@@ -101,11 +101,10 @@ namespace wren {
     assert(!Texture2d::cachedItemCount());
   }
 
-  void Scene::getMainBuffer(int width, int height, unsigned int format, unsigned int data_type, unsigned int buffer_type,
-                            void *buffer) {
-    assert(buffer_type == GL_FRONT || buffer_type == GL_BACK);
-    glstate::bindFrameBuffer(0);
-    glReadBuffer(buffer_type);
+  void Scene::getMainBuffer(int width, int height, unsigned int format, unsigned int data_type, void *buffer) {
+    glstate::bindFrameBuffer(instance()->mMainViewport->frameBuffer()->glName());
+    glReadBuffer(GL_COLOR_ATTACHMENT0);
+    glFinish();
     glReadPixels(0, 0, width, height, format, data_type, buffer);
   }
 
@@ -884,9 +883,8 @@ void wr_scene_apply_pending_updates(WrScene *scene) {
   reinterpret_cast<wren::Scene *>(scene)->applyPendingUpdates();
 }
 
-void wr_scene_get_main_buffer(WrScene *scene, int width, int height, unsigned int format, unsigned int data_type,
-                              unsigned int buffer_type, void *buffer) {
-  reinterpret_cast<wren::Scene *>(scene)->getMainBuffer(width, height, format, data_type, buffer_type, buffer);
+void wr_scene_get_main_buffer(int width, int height, unsigned int format, unsigned int data_type, void *buffer) {
+  wren::Scene::getMainBuffer(width, height, format, data_type, buffer);
 }
 
 void wr_scene_init_frame_capture(WrScene *scene, int pixel_buffer_count, unsigned int *pixel_buffer_ids, int frame_size) {

src/wren/Scene.hpp

@@ -53,8 +53,7 @@ namespace wren {
     void reset();
     static void applyPendingUpdates();
 
-    static void getMainBuffer(int width, int height, unsigned int format, unsigned int data_type, unsigned int buffer_type,
-                              void *buffer);
+    static void getMainBuffer(int width, int height, unsigned int format, unsigned int data_type, void *buffer);
     void initFrameCapture(int pixelBufferCount, unsigned int *pixelBufferIds, int frameSize);
     static void bindPixelBuffer(int buffer);
     void *mapPixelBuffer(unsigned int accessMode);

tests/Makefile

@@ -12,9 +12,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-.PHONY: api cache other_api parser physics protos rendering with_rendering
+.PHONY: api cache other_api parser physics protos rendering
 
-release debug profile: api cache other_api parser physics protos rendering with_rendering
+release debug profile: api cache other_api parser physics protos rendering
 
 clean: api cache parser physics protos rendering
 	@-rm -rf *.txt \
@@ -56,6 +56,3 @@ protos:
 
 rendering:
 	+@make -s -C rendering $(MAKECMDGOALS)
-
-with_rendering:
-	+@make -s -C with_rendering $(MAKECMDGOALS)

tests/test_suite.py

@@ -50,7 +50,7 @@
 parser.add_argument('--nomake', dest='nomake', default=False, action='store_true', help='The controllers are not re-compiled.')
 parser.add_argument('--no-ansi-escape', dest='ansi_escape', default=True, action='store_false', help='Disables ansi escape.')
 parser.add_argument('--group', '-g', type=str, dest='group', default=[], help='Specifies which group of tests should be run.',
-                    choices=['api', 'cache', 'other_api', 'physics', 'protos', 'parser', 'rendering', 'with_rendering'])
+                    choices=['api', 'cache', 'other_api', 'physics', 'protos', 'parser', 'rendering'])
 parser.add_argument('--performance-log', '-p', type=str, dest='performance_log', default="",
                     help='The name of the performance log file to use if you want to log performance.')
 parser.add_argument('worlds', nargs='*', default=[])
@@ -236,11 +236,9 @@ def runGroupTest(groupName, firstSimulation, worldsCount, failures):
     #  command.run(silent = False)
 
     webotsArguments = [webotsFullPath, firstSimulation]
-    webotsArguments += ['--mode=fast', '--stdout', '--stderr', '--batch']
+    webotsArguments += ['--mode=fast', '--stdout', '--stderr', '--batch', '--no-rendering', '--minimize']
     if args.performance_log:
         webotsArguments += [f'--log-performance={args.performance_log}']
-    if groupName != 'with_rendering':
-        webotsArguments += ['--no-rendering', '--minimize']
     if groupName == 'cache':
         webotsArguments += ['--clear-cache']
     command = Command(webotsArguments)
@@ -332,7 +330,7 @@ def runGroupTest(groupName, firstSimulation, worldsCount, failures):
 if args.group:
     testGroups = [str(args.group)]
 else:
-    testGroups = ['api', 'cache', 'other_api', 'physics', 'protos', 'parser', 'rendering', 'with_rendering']
+    testGroups = ['api', 'cache', 'other_api', 'physics', 'protos', 'parser', 'rendering']
 
 if sys.platform == 'win32' and 'parser' in testGroups:
     testGroups.remove('parser')  # this one doesn't work on Windows