Cleanup: Remove no-op node preview function calls

This patch removes no-op node editor preview code (`PR_NODE_RENDER`)
and most calls to `BKE_node_preview_init_tree`. The only remaining call is
in the compositor.

 - Shader nodes previews don't seem to do anything.
 - In-node previews for the texture node system doesn't work either.

This is a first step to refactoring to remove `preview_xsize`,
`preview_ysize`, and `prvr` from nodes in DNA, aligned with
the general goal of removing runtime/derived data from data
structs.

Differential Revision: https://developer.blender.org/D13578

1 files changed, 3 insertions, 84 deletions

diff --git a/source/blender/editors/render/render_preview.c b/source/blender/editors/render/render_preview.c
index e1121aa4b1e..9ff1fc89350 100644
--- a/source/blender/editors/render/render_preview.c
+++ b/source/blender/editors/render/render_preview.c
@@ -214,7 +214,7 @@ static bool check_engine_supports_preview(Scene *scene)
 
 static bool preview_method_is_render(int pr_method)
 {
-  return ELEM(pr_method, PR_ICON_RENDER, PR_BUTS_RENDER, PR_NODE_RENDER);
+  return ELEM(pr_method, PR_ICON_RENDER, PR_BUTS_RENDER);
 }
 
 void ED_preview_free_dbase(void)
@@ -528,15 +528,6 @@ static Scene *preview_prepare_scene(
                                               MA_SPHERE_A :
                                               mat->pr_type;
         set_preview_visibility(pr_main, sce, view_layer, preview_type, sp->pr_method);
-
-        if (sp->pr_method != PR_ICON_RENDER) {
-          if (mat->nodetree && sp->pr_method == PR_NODE_RENDER) {
-            /* two previews, they get copied by wmJob */
-            BKE_node_preview_init_tree(mat->nodetree, sp->sizex, sp->sizey, true);
-            /* WATCH: Accessing origmat is not safe! */
-            BKE_node_preview_init_tree(origmat->nodetree, sp->sizex, sp->sizey, true);
-          }
-        }
       }
       else {
         sce->display.render_aa = SCE_DISPLAY_AA_OFF;
@@ -572,13 +563,6 @@ static Scene *preview_prepare_scene(
         sp->id_copy = NULL;
         BLI_addtail(&pr_main->textures, tex);
       }
-
-      if (tex && tex->nodetree && sp->pr_method == PR_NODE_RENDER) {
-        /* two previews, they get copied by wmJob */
-        BKE_node_preview_init_tree(tex->nodetree, sp->sizex, sp->sizey, true);
-        /* WATCH: Accessing origtex is not safe! */
-        BKE_node_preview_init_tree(origtex->nodetree, sp->sizex, sp->sizey, true);
-      }
     }
     else if (id_type == ID_LA) {
       Light *la = NULL, *origla = (Light *)id;
@@ -608,13 +592,6 @@ static Scene *preview_prepare_scene(
           }
         }
       }
-
-      if (la && la->nodetree && sp->pr_method == PR_NODE_RENDER) {
-        /* two previews, they get copied by wmJob */
-        BKE_node_preview_init_tree(la->nodetree, sp->sizex, sp->sizey, true);
-        /* WATCH: Accessing origla is not safe! */
-        BKE_node_preview_init_tree(origla->nodetree, sp->sizex, sp->sizey, true);
-      }
     }
     else if (id_type == ID_WO) {
       World *wrld = NULL, *origwrld = (World *)id;
@@ -628,13 +605,6 @@ static Scene *preview_prepare_scene(
 
       set_preview_visibility(pr_main, sce, view_layer, MA_SKY, sp->pr_method);
       sce->world = wrld;
-
-      if (wrld && wrld->nodetree && sp->pr_method == PR_NODE_RENDER) {
-        /* two previews, they get copied by wmJob */
-        BKE_node_preview_init_tree(wrld->nodetree, sp->sizex, sp->sizey, true);
-        /* WATCH: Accessing origwrld is not safe! */
-        BKE_node_preview_init_tree(origwrld->nodetree, sp->sizex, sp->sizey, true);
-      }
     }
 
     return sce;
@@ -1037,41 +1007,8 @@ static int shader_preview_break(void *spv)
   return *(sp->stop);
 }
 
-/* outside thread, called before redraw notifiers, it moves finished preview over */
-static void shader_preview_updatejob(void *spv)
+static void shader_preview_updatejob(void *UNUSED(spv))
 {
-  ShaderPreview *sp = spv;
-
-  if (sp->pr_method == PR_NODE_RENDER) {
-    if (GS(sp->id->name) == ID_MA) {
-      Material *mat = (Material *)sp->id;
-
-      if (sp->matcopy && mat->nodetree && sp->matcopy->nodetree) {
-        ntreeLocalSync(sp->matcopy->nodetree, mat->nodetree);
-      }
-    }
-    else if (GS(sp->id->name) == ID_TE) {
-      Tex *tex = (Tex *)sp->id;
-
-      if (sp->texcopy && tex->nodetree && sp->texcopy->nodetree) {
-        ntreeLocalSync(sp->texcopy->nodetree, tex->nodetree);
-      }
-    }
-    else if (GS(sp->id->name) == ID_WO) {
-      World *wrld = (World *)sp->id;
-
-      if (sp->worldcopy && wrld->nodetree && sp->worldcopy->nodetree) {
-        ntreeLocalSync(sp->worldcopy->nodetree, wrld->nodetree);
-      }
-    }
-    else if (GS(sp->id->name) == ID_LA) {
-      Light *la = (Light *)sp->id;
-
-      if (sp->lampcopy && la->nodetree && sp->lampcopy->nodetree) {
-        ntreeLocalSync(sp->lampcopy->nodetree, la->nodetree);
-      }
-    }
-  }
 }
 
 /* Renders texture directly to render buffer. */
@@ -1187,21 +1124,12 @@ static void shader_preview_render(ShaderPreview *sp, ID *id, int split, int firs
     sce->r.scemode |= R_NO_IMAGE_LOAD;
     sce->display.render_aa = SCE_DISPLAY_AA_SAMPLES_8;
   }
-  else if (sp->pr_method == PR_NODE_RENDER) {
-    if (idtype == ID_MA) {
-      sce->r.scemode |= R_MATNODE_PREVIEW;
-    }
-    else if (idtype == ID_TE) {
-      sce->r.scemode |= R_TEXNODE_PREVIEW;
-    }
-    sce->display.render_aa = SCE_DISPLAY_AA_OFF;
-  }
   else { /* PR_BUTS_RENDER */
     sce->display.render_aa = SCE_DISPLAY_AA_SAMPLES_8;
   }
 
   /* Callbacks are cleared on GetRender(). */
-  if (ELEM(sp->pr_method, PR_BUTS_RENDER, PR_NODE_RENDER)) {
+  if (sp->pr_method == PR_BUTS_RENDER) {
     RE_display_update_cb(re, sp, shader_preview_update);
   }
   /* set this for all previews, default is react to G.is_break still */
@@ -1309,10 +1237,6 @@ static void shader_preview_free(void *customdata)
     main_id_copy = (ID *)sp->lampcopy;
     BLI_remlink(&pr_main->lights, sp->lampcopy);
   }
-  if (main_id_copy || sp->id_copy) {
-    /* node previews */
-    shader_preview_updatejob(sp);
-  }
   if (sp->own_id_copy) {
     if (sp->id_copy) {
       preview_id_copy_free(sp->id_copy);
@@ -1882,11 +1806,6 @@ void ED_preview_shader_job(const bContext *C,
     return;
   }
 
-  /* Only texture node preview is supported with Cycles. */
-  if (method == PR_NODE_RENDER && id_type != ID_TE) {
-    return;
-  }
-
   ED_preview_ensure_dbase();
 
   wm_job = WM_jobs_get(CTX_wm_manager(C),