expose texture unique id after loading URD file, so you can restore to the original texture after changing it to a custom texture. See also getTextureUid.py example.

examples/pybullet/examples/getTextureUid.py

@@ -0,0 +1,19 @@
+import pybullet as p
+p.connect(p.GUI)
+plane = p.loadURDF("plane.urdf")
+visualData = p.getVisualShapeData(plane, p.VISUAL_SHAPE_DATA_TEXTURE_UNIQUE_IDS)
+print(visualData)
+curTexUid = visualData[0][8]
+print(curTexUid)
+texUid = p.loadTexture("tex256.png")
+print("texUid=",texUid)
+
+p.changeVisualShape(plane,-1,textureUniqueId=texUid)
+
+for i in range (100):
+	p.getCameraImage(320,200)
+p.changeVisualShape(plane,-1,textureUniqueId=curTexUid)
+
+for i in range (100):
+	p.getCameraImage(320,200)
+