Allows to specify render callback. (#150)

Author: wojzaremba

examples/render_callback.py

@@ -0,0 +1,28 @@
+#!/usr/bin/env python3
+"""
+Shows how to use render callback.
+"""
+from mujoco_py import load_model_from_path, MjSim, MjViewer
+from mujoco_py.modder import TextureModder
+import os
+
+modder = None
+def render_callback(sim, viewer):
+    global modder
+    if modder is None:
+        modder = TextureModder(sim)
+    for name in sim.model.geom_names:
+        modder.rand_all(name)
+
+model = load_model_from_path("xmls/fetch/main.xml")
+sim = MjSim(model, render_callback=render_callback)
+
+viewer = MjViewer(sim)
+
+t = 0
+
+while True:
+    viewer.render()
+    t += 1
+    if t > 100 and os.getenv('TESTING') is not None:
+        break

mujoco_py/mjrendercontext.pyx

@@ -120,6 +120,9 @@ cdef class MjRenderContext(object):
         rect.width = width
         rect.height = height
 
+        if self.sim.render_callback is not None:
+            self.sim.render_callback(self.sim, self)
+
         # Sometimes buffers are too small.
         if width > self._con.offWidth or height > self._con.offHeight:
             new_width = max(width, self._model_ptr.vis.global_.offwidth)

mujoco_py/mjsim.pyx

@@ -38,6 +38,7 @@ cdef class MjSim(object):
     userdata_names : list of strings or None
         This is a convenience parameter which is just set on the model.
         Equivalent to calling ``model.set_userdata_names``
+    render_callback : callback for rendering.
     """
     # MjRenderContext for rendering camera views.
     cdef readonly list render_contexts
@@ -61,9 +62,12 @@ cdef class MjSim(object):
     cdef readonly dict extras
     # Function pointer for substep callback, stored as uintptr
     cdef readonly uintptr_t substep_callback_ptr
+    # Callback executed before rendering.
+    cdef public object render_callback
 
     def __cinit__(self, PyMjModel model, PyMjData data=None, int nsubsteps=1,
-                  udd_callback=None, substep_callback=None, userdata_names=None):
+                  udd_callback=None, substep_callback=None, userdata_names=None,
+                  render_callback=None):
         self.nsubsteps = nsubsteps
         self.model = model
         if data is None:
@@ -80,6 +84,7 @@ cdef class MjSim(object):
         self._render_context_window = None
         self.udd_state = None
         self.udd_callback = udd_callback
+        self.render_callback = render_callback
         self.extras = {}
         self.set_substep_callback(substep_callback, userdata_names)
 

mujoco_py/mjviewer.py

@@ -175,7 +175,6 @@ def render_inner_loop(self):
                 for k, v in self._user_overlay.items():
                     self._overlay[k] = copy.deepcopy(v)
                 self._create_full_overlay()
-
             super().render()
             if self._record_video:
                 frame = self._read_pixels_as_in_window()

mujoco_py/version.py

@@ -1,6 +1,6 @@
 __all__ = ['__version__', 'get_version']
 
-version_info = (1, 50, 1, 23)
+version_info = (1, 50, 1, 24)
 # format:
 # ('mujoco_major', 'mujoco_minor', 'mujoco_py_major', 'mujoco_py_minor')