Added a button to the UI of "Distance from Camera" color/alpha/thickness

modifiers to fill the Range Min/Max entries by the min/max distance between
selected mesh objects and the active camera.

release/scripts/startup/bl_operators/__init__.py

@@ -25,6 +25,7 @@ if "bpy" in locals():
 _modules = (
     "add_mesh_torus",
     "animsys_update",
+    "freestyle",
     "image",
     "mesh",
     "nla",

release/scripts/startup/bl_operators/freestyle.py

@@ -0,0 +1,62 @@
+# ##### BEGIN GPL LICENSE BLOCK #####
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU General Public License
+#  as published by the Free Software Foundation; either version 2
+#  of the License, or (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program; if not, write to the Free Software Foundation,
+#  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# ##### END GPL LICENSE BLOCK #####
+
+import bpy
+
+from bpy.props import (EnumProperty, StringProperty)
+
+
+class SCENE_OT_freestyle_fill_range_by_selection(bpy.types.Operator):
+    '''Fill the Range Min/Max entries by the min/max distance between selected mesh objects and the active camera.'''
+    bl_idname = "scene.freestyle_fill_range_by_selection"
+    bl_label = "Fill Range by Selection"
+
+    type = EnumProperty(name="Type", description="Type of the modifier to work on.",
+                        items=[("COLOR", "Color", "Color modifier type."),
+                               ("ALPHA", "Alpha", "Alpha modifier type."),
+                               ("THICKNESS", "Thickness", "Thickness modifier type.")])
+    name = StringProperty(name="Name", description="Name of the modifier to work on.")
+
+    def execute(self, context):
+        rl = context.scene.render.layers.active
+        lineset = rl.freestyle_settings.linesets.active
+        linestyle = lineset.linestyle
+        # Find the modifier to work on
+        if self.type == 'COLOR':
+            m = linestyle.color_modifiers[self.name]
+        elif self.type == 'ALPHA':
+            m = linestyle.alpha_modifiers[self.name]
+        else:
+            m = linestyle.thickness_modifiers[self.name]
+        # Find the active camera
+        camera = context.scene.camera
+        # Find selected mesh objects
+        selection = [ob for ob in context.scene.objects if ob.select and ob.type == 'MESH']
+        if len(selection) > 0:
+            # Compute the min/max distance between selected mesh objects and the camera
+            min_dist = float('inf')
+            max_dist = -min_dist
+            for ob in selection:
+                for vert in ob.data.vertices:
+                    dist = (ob.matrix_world * vert.co - camera.location).length
+                    min_dist = min(dist, min_dist)
+                    max_dist = max(dist, max_dist)
+            # Fill the Range Min/Max entries with the computed distances
+            m.range_min = min_dist
+            m.range_max = max_dist
+        return {'FINISHED'}

release/scripts/startup/bl_ui/properties_render.py

@@ -366,6 +366,9 @@ class RENDER_PT_freestyle_linestyle(RenderButtonsPanel, bpy.types.Panel):
 
             elif modifier.type == "DISTANCE_FROM_CAMERA":
                 self.draw_modifier_color_ramp_common(box, modifier, True)
+                prop = box.operator("scene.freestyle_fill_range_by_selection")
+                prop.type = 'COLOR'
+                prop.name = modifier.name
 
             elif modifier.type == "MATERIAL":
                 row = box.row()
@@ -399,6 +402,9 @@ class RENDER_PT_freestyle_linestyle(RenderButtonsPanel, bpy.types.Panel):
 
             elif modifier.type == "DISTANCE_FROM_CAMERA":
                 self.draw_modifier_curve_common(box, modifier, True, False)
+                prop = box.operator("scene.freestyle_fill_range_by_selection")
+                prop.type = 'ALPHA'
+                prop.name = modifier.name
 
             elif modifier.type == "MATERIAL":
                 box.prop(modifier, "material_attr", text="")
@@ -422,6 +428,9 @@ class RENDER_PT_freestyle_linestyle(RenderButtonsPanel, bpy.types.Panel):
 
             elif modifier.type == "DISTANCE_FROM_CAMERA":
                 self.draw_modifier_curve_common(box, modifier, True, True)
+                prop = box.operator("scene.freestyle_fill_range_by_selection")
+                prop.type = 'THICKNESS'
+                prop.name = modifier.name
 
             elif modifier.type == "MATERIAL":
                 box.prop(modifier, "material_attr", text="")