Remove Blender Internal and legacy viewport from Blender 2.8.

Brecht authored this commit, but he gave me the honours to actually
do it. Here it goes; Blender Internal. Bye bye, you did great!

* Point density, voxel data, ocean, environment map textures were removed,
  as these only worked within BI rendering. Note that the ocean modifier
  and the Cycles point density shader node continue to work.
* Dynamic paint using material shading was removed, as this only worked
  with BI. If we ever wanted to support this again probably it should go
  through the baking API.
* GPU shader export through the Python API was removed. This only worked
  for the old BI GLSL shaders, which no longer exists. Doing something
  similar for Eevee would be significantly more complicated because it
  uses a lot of multiplass rendering and logic outside the shader, it's
  probably impractical.
* Collada material import / export code is mostly gone, as it only worked
  for BI materials. We need to add Cycles / Eevee material support at some
  point.
* The mesh noise operator was removed since it only worked with BI
  material texture slots. A displacement modifier can be used instead.
* The delete texture paint slot operator was removed since it only worked
  for BI material texture slots. Could be added back with node support.

* Not all legacy viewport features are supported in the new viewport, but
  their code was removed. If we need to bring anything back we can look at
  older git revisions.
* There is some legacy viewport code that I could not remove yet, and some
  that I probably missed.
* Shader node execution code was left mostly intact, even though it is not
  used anywhere now. We may eventually use this to replace the texture
  nodes with Cycles / Eevee shader nodes.

* The Cycles Bake panel now includes settings for baking multires normal
  and displacement maps. The underlying code needs to be merged properly,
  and we plan to add back support for multires AO baking and add support
  to Cycles baking for features like vertex color, displacement, and other
  missing baking features.

* This commit removes DNA and the Python API for BI material, lamp, world
  and scene settings. This breaks a lot of addons.
* There is more DNA that can be removed or renamed, where Cycles or Eevee
  are reusing some old BI properties but the names are not really correct
  anymore.
* Texture slots for materials, lamps and world were removed. They remain
  for brushes, particles and freestyle linestyles.
* 'BLENDER_RENDER' remains in the COMPAT_ENGINES of UI panels. Cycles and
  other renderers use this to find all panels to show, minus a few panels
  that they have their own replacement for.

1 files changed, 6 insertions, 8 deletions

diff --git a/release/scripts/startup/bl_ui/space_node.py b/release/scripts/startup/bl_ui/space_node.py
index 8b199d7eef1..f97c88be0ad 100644
--- a/release/scripts/startup/bl_ui/space_node.py
+++ b/release/scripts/startup/bl_ui/space_node.py
@@ -51,14 +51,12 @@ class NODE_HT_header(Header):
         NODE_MT_editor_menus.draw_collapsible(context, layout)
 
         layout.prop(snode, "tree_type", text="", expand=True)
-        use_shading_nodes = scene.render.use_shading_nodes
 
         if snode.tree_type == 'ShaderNodeTree':
-            if use_shading_nodes:
-                layout.prop(snode, "shader_type", text="", expand=True)
+            layout.prop(snode, "shader_type", text="", expand=True)
 
             ob = context.object
-            if (not use_shading_nodes or snode.shader_type == 'OBJECT') and ob:
+            if snode.shader_type == 'OBJECT' and ob:
                 row = layout.row()
                 # disable material slot buttons when pinned, cannot find correct slot within id_from (#36589)
                 row.enabled = not snode.pin
@@ -69,18 +67,18 @@ class NODE_HT_header(Header):
                 if id_from and ob.type != 'LAMP':
                     row.template_ID(id_from, "active_material", new="material.new")
 
-                # Don't show "Use Nodes" Button when Engine is BI for Lamps
-                if snode_id and not (use_shading_nodes == 0 and ob.type == 'LAMP'):
+                # No shader nodes for Eevee lamps
+                if snode_id and not (context.engine == 'BLENDER_EEVEE' and ob.type == 'LAMP'):
                     layout.prop(snode_id, "use_nodes")
 
-            if use_shading_nodes and snode.shader_type == 'WORLD':
+            if snode.shader_type == 'WORLD':
                 row = layout.row()
                 row.enabled = not snode.pin
                 row.template_ID(scene, "world", new="world.new")
                 if snode_id:
                     row.prop(snode_id, "use_nodes")
 
-            if use_shading_nodes and snode.shader_type == 'LINESTYLE':
+            if snode.shader_type == 'LINESTYLE':
                 view_layer = context.scene.view_layers.active
                 lineset = view_layer.freestyle_settings.linesets.active
                 if lineset is not None: