Fix T52344: Softbody on Text.

Own previous fix (rBd5d626df236b) was not valid, curves are actually
supported by SoftBodies. It was rather a mere UI bug, which was not
including Surfaces and Font obect types in those valid for softbody UI.

Thanks to @brecht for the head up!

Also, fix safe for 2.79, btw.

release/scripts/startup/bl_ui/properties_physics_common.py

@@ -79,7 +79,7 @@ class PHYSICS_PT_add(PhysicButtonsPanel, Panel):
 
         col = split.column()
 
-        if obj.type in {'MESH', 'LATTICE', 'CURVE'}:
+        if obj.type in {'MESH', 'LATTICE', 'CURVE', 'SURFACE', 'FONT'}:
             physics_add(self, col, context.soft_body, "Soft Body", 'SOFT_BODY', 'MOD_SOFT', True)
 
         if obj.type == 'MESH':

release/scripts/startup/bl_ui/properties_physics_softbody.py

@@ -26,6 +26,9 @@ from bl_ui.properties_physics_common import (
         )
 
 
+COMPAT_OB_TYPES = {'MESH', 'LATTICE', 'CURVE', 'SURFACE', 'FONT'}
+
+
 def softbody_panel_enabled(md):
     return (md.point_cache.is_baked is False)
 
@@ -39,7 +42,7 @@ class PhysicButtonsPanel:
     def poll(cls, context):
         ob = context.object
         rd = context.scene.render
-        return (ob and (ob.type == 'MESH' or ob.type == 'LATTICE'or ob.type == 'CURVE')) and (rd.engine in cls.COMPAT_ENGINES) and (context.soft_body)
+        return ob and ob.type in COMPAT_OB_TYPES and rd.engine in cls.COMPAT_ENGINES and context.soft_body
 
 
 class PHYSICS_PT_softbody(PhysicButtonsPanel, Panel):

source/blender/modifiers/intern/MOD_softbody.c

@@ -100,7 +100,8 @@ ModifierTypeInfo modifierType_Softbody = {
 	/* structName */        "SoftbodyModifierData",
 	/* structSize */        sizeof(SoftbodyModifierData),
 	/* type */              eModifierTypeType_OnlyDeform,
-	/* flags */             eModifierTypeFlag_AcceptsLattice |
+	/* flags */             eModifierTypeFlag_AcceptsCVs |
+	                        eModifierTypeFlag_AcceptsLattice |
 	                        eModifierTypeFlag_RequiresOriginalData |
 	                        eModifierTypeFlag_Single,