Cycles API: encapsulate Node socket members

This encapsulates Node socket members behind a set of specific methods;
as such it is no longer possible to directly access Node class members
from exporters and parts of Cycles.

The methods are defined via the NODE_SOCKET_API macros in `graph/
node.h`, and are for getting or setting a specific socket's value, as
well as querying or modifying the state of its update flag.

The setters will check whether the value has changed and tag the socket
as modified appropriately. This will let us know how a Node has changed
and what to update, which is the first concrete step toward a more
granular scene update system.

Since the setters will tag the Node sockets as modified when passed
different data, this patch also removes the various `modified` methods
on Nodes in favor of `Node::is_modified` which checks the sockets'
update flags status.

Reviewed By: brecht

Maniphest Tasks: T79174

Differential Revision: https://developer.blender.org/D8544

1 files changed, 33 insertions, 27 deletions

diff --git a/intern/cycles/render/light.h b/intern/cycles/render/light.h
index d136e8f1a08..e590e13b489 100644
--- a/intern/cycles/render/light.h
+++ b/intern/cycles/render/light.h
@@ -21,6 +21,10 @@
 
 #include "graph/node.h"
 
+/* included as Light::set_shader defined through NODE_SOCKET_API does not select
+ * the right Node::set overload as it does not know that Shader is a Node */
+#include "render/shader.h"
+
 #include "util/util_ies.h"
 #include "util/util_thread.h"
 #include "util/util_types.h"
@@ -41,46 +45,48 @@ class Light : public Node {
 
   Light();
 
-  LightType type;
-  float3 strength;
-  float3 co;
+  NODE_SOCKET_API(LightType, light_type)
+  NODE_SOCKET_API(float3, strength)
+  NODE_SOCKET_API(float3, co)
 
-  float3 dir;
-  float size;
-  float angle;
+  NODE_SOCKET_API(float3, dir)
+  NODE_SOCKET_API(float, size)
+  NODE_SOCKET_API(float, angle)
 
-  float3 axisu;
-  float sizeu;
-  float3 axisv;
-  float sizev;
-  bool round;
+  NODE_SOCKET_API(float3, axisu)
+  NODE_SOCKET_API(float, sizeu)
+  NODE_SOCKET_API(float3, axisv)
+  NODE_SOCKET_API(float, sizev)
+  NODE_SOCKET_API(bool, round)
 
-  Transform tfm;
+  NODE_SOCKET_API(Transform, tfm)
 
-  int map_resolution;
+  NODE_SOCKET_API(int, map_resolution)
 
-  float spot_angle;
-  float spot_smooth;
+  NODE_SOCKET_API(float, spot_angle)
+  NODE_SOCKET_API(float, spot_smooth)
 
-  bool cast_shadow;
-  bool use_mis;
-  bool use_diffuse;
-  bool use_glossy;
-  bool use_transmission;
-  bool use_scatter;
+  NODE_SOCKET_API(bool, cast_shadow)
+  NODE_SOCKET_API(bool, use_mis)
+  NODE_SOCKET_API(bool, use_diffuse)
+  NODE_SOCKET_API(bool, use_glossy)
+  NODE_SOCKET_API(bool, use_transmission)
+  NODE_SOCKET_API(bool, use_scatter)
 
-  bool is_portal;
-  bool is_enabled;
+  NODE_SOCKET_API(bool, is_portal)
+  NODE_SOCKET_API(bool, is_enabled)
 
-  Shader *shader;
-  int samples;
-  int max_bounces;
-  uint random_id;
+  NODE_SOCKET_API(Shader *, shader)
+  NODE_SOCKET_API(int, samples)
+  NODE_SOCKET_API(int, max_bounces)
+  NODE_SOCKET_API(uint, random_id)
 
   void tag_update(Scene *scene);
 
   /* Check whether the light has contribution the scene. */
   bool has_contribution(Scene *scene);
+
+  friend class LightManager;
 };
 
 class LightManager {