Fixing the constant buffers containing the scene data being GPU uploaded while the wrong context was enabled

Author: AnisB

genesis/ext/pyrender/offscreen.py

@@ -34,6 +34,7 @@ def __init__(self, point_size=1.0, pyopengl_platform="pyglet", seg_node_map=None
         self.point_size = point_size
         self._platform = None
         self._is_software = False
+        self._has_valid_context = False
         self._create(pyopengl_platform)
         self._seg_node_map = seg_node_map
 
@@ -66,6 +67,38 @@ def point_size(self):
     def point_size(self, value):
         self._point_size = float(value)
 
+    def make_current(self):
+        """This function sets the current context and must be called before all rendering and GPU upload operations.
+        """
+        if self._has_valid_context:
+            gs.raise_exception("The method was called while having an other context current. Please call 'make_uncurrent' first.")
+
+        self._platform.make_current()
+
+        # If platform does not support dynamically-resizing framebuffers,
+        # destroy it and restart it
+        if (
+            self._platform.viewport_height != self.viewport_height
+            or self._platform.viewport_width != self.viewport_width
+        ):
+            if not self._platform.supports_framebuffers():
+                self.delete()
+                self._create()
+
+                # Only needs to happen if the context was deleted and created
+                self._platform.make_current()
+
+        self._has_valid_context = True
+
+    def make_uncurrent(self):
+        """This function unsets the current context and must be called after all rendering and GPU upload operations
+        are done.
+        """
+        if not self._has_valid_context:
+            gs.raise_exception("The method was called before making a context current.")
+        self._platform.make_uncurrent()
+        self._has_valid_context = False
+
     def render(
         self,
         scene,
@@ -97,24 +130,13 @@ def render(
         depth_im : (h, w) float32
             The depth buffer in linear units.
         """
+        if not self._has_valid_context:
+            gs.raise_exception("Ensure that the right context is set before rendering. Please call the method 'make_current'.")
 
         if camera_node is not None:
             saved_camera_node = scene.main_camera_node
             scene.main_camera_node = camera_node
 
-        self._platform.make_current()
-        # If platform does not support dynamically-resizing framebuffers,
-        # destroy it and restart it
-        if (
-            self._platform.viewport_height != self.viewport_height
-            or self._platform.viewport_width != self.viewport_width
-        ):
-            if not self._platform.supports_framebuffers():
-                self.delete()
-                self._create()
-
-        self._platform.make_current()
-
         # Forcibly disable shadow for software rendering as it may hang indefinitely
         if shadow and not self._is_software:
             flags |= RenderFlags.SHADOWS_ALL
@@ -172,9 +194,6 @@ def get_program(self, vertex_shader, fragment_shader, geometry_shader=None, defi
 
             renderer._program_cache = old_cache
 
-        # Make the platform not current
-        self._platform.make_uncurrent()
-
         if camera_node is not None:
             scene.main_camera_node = saved_camera_node
 

genesis/vis/rasterizer.py

@@ -18,6 +18,7 @@ def __init__(self, viewer, context):
         self._camera_targets = dict()
         self._offscreen = self._viewer is None
         self._renderer = None
+        self._buffer_updates = None
 
     def build(self):
         if self._context is None:
@@ -57,6 +58,16 @@ def remove_camera(self, camera):
     def render_camera(self, camera, rgb=True, depth=False, segmentation=False, normal=False):
         rgb_arr, depth_arr, seg_idxc_arr, normal_arr = None, None, None, None
         if self._offscreen:
+            # Set the context
+            self._renderer.make_current()
+
+            # Update the buffers
+            if self._buffer_updates is None:
+                gs.raise_exception("Buffers were not set before rendering. Please call 'update_scene' method.")
+
+            self._context.jit.update_buffer(self._buffer_updates)
+
+            # Render
             if rgb or depth or normal:
                 retval = self._renderer.render(
                     self._context._scene,
@@ -82,7 +93,14 @@ def render_camera(self, camera, rgb=True, depth=False, segmentation=False, norma
                     normal=False,
                     seg=True,
                 )
+
+            # Unset the context
+            self._renderer.make_uncurrent()
         else:
+            # Update the buffers
+            self._context.jit.update_buffer(self._buffer_updates)
+
+            # Render
             if rgb or depth or normal:
                 retval = self._viewer._pyrender_viewer.render_offscreen(
                     self._camera_nodes[camera.uid],
@@ -111,8 +129,7 @@ def render_camera(self, camera, rgb=True, depth=False, segmentation=False, norma
         return rgb_arr, depth_arr, seg_idxc_arr, normal_arr
 
     def update_scene(self):
-        buffer_updates = self._context.update()
-        self._context.jit.update_buffer(buffer_updates)
+        self._buffer_updates = self._context.update()
 
     def destroy(self):
         for node in self._camera_nodes.values():

genesis/vis/visualizer.py

@@ -156,6 +156,7 @@ def build(self):
                 self._viewer.update(auto_refresh=True)
             else:
                 # viewer creation will compile rendering kernels if viewer is not created, render here once to compile
+                self._rasterizer.update_scene()
                 self._rasterizer.render_camera(self._cameras[0])
 
     def update(self, force=True, auto=None):