MeshRasterizerOpenGL import fixes

Summary: Only import it if you ask for it.

Reviewed By: kjchalup

Differential Revision: D38327167

fbshipit-source-id: 3f05231f26eda582a63afc71b669996342b0c6f9

pytorch3d/renderer/__init__.py

@@ -65,11 +65,6 @@ from .mesh import (
     TexturesVertex,
 )
 
-try:
-    from .opengl import EGLContext, global_device_context_store, MeshRasterizerOpenGL
-except (ImportError, ModuleNotFoundError):
-    pass  # opengl or pycuda.gl not available, or pytorch3_opengl not in TARGETS.
-
 from .points import (
     AlphaCompositor,
     NormWeightedCompositor,

pytorch3d/renderer/mesh/renderer.py

@@ -10,8 +10,6 @@ import torch
 import torch.nn as nn
 
 from ...structures.meshes import Meshes
-from .rasterizer import MeshRasterizer
-
 
 # A renderer class should be initialized with a
 # function for rasterization and a function for shading.
@@ -32,11 +30,11 @@ from .rasterizer import MeshRasterizer
 class MeshRenderer(nn.Module):
     """
     A class for rendering a batch of heterogeneous meshes. The class should
-    be initialized with a rasterizer and shader class which each have a forward
-    function.
+    be initialized with a rasterizer (a MeshRasterizer or a MeshRasterizerOpenGL)
+    and shader class which each have a forward function.
     """
 
-    def __init__(self, rasterizer: MeshRasterizer, shader) -> None:
+    def __init__(self, rasterizer, shader) -> None:
         super().__init__()
         self.rasterizer = rasterizer
         self.shader = shader
@@ -69,8 +67,8 @@ class MeshRenderer(nn.Module):
 class MeshRendererWithFragments(nn.Module):
     """
     A class for rendering a batch of heterogeneous meshes. The class should
-    be initialized with a rasterizer and shader class which each have a forward
-    function.
+    be initialized with a rasterizer (a MeshRasterizer or a MeshRasterizerOpenGL)
+    and shader class which each have a forward function.
 
     In the forward pass this class returns the `fragments` from which intermediate
     values such as the depth map can be easily extracted e.g.
@@ -80,7 +78,7 @@ class MeshRendererWithFragments(nn.Module):
         depth = fragments.zbuf
     """
 
-    def __init__(self, rasterizer: MeshRasterizer, shader) -> None:
+    def __init__(self, rasterizer, shader) -> None:
         super().__init__()
         self.rasterizer = rasterizer
         self.shader = shader

pytorch3d/renderer/opengl/rasterizer_opengl.py

@@ -130,8 +130,9 @@ class MeshRasterizerOpenGL(nn.Module):
 
     Fragments output by MeshRasterizerOpenGL and MeshRasterizer should have near
     identical pix_to_face, bary_coords and zbuf. However, MeshRasterizerOpenGL does not
-    return Fragments.dists which is only relevant to SoftPhongShader which doesn't work
-    with MeshRasterizerOpenGL (because it is not differentiable).
+    return Fragments.dists which is only relevant to SoftPhongShader and
+    SoftSilhouetteShader. These do not work with MeshRasterizerOpenGL (because it is
+    not differentiable).
     """
 
     def __init__(