curve_tools/show_resolution.py

   1 # SPDX-FileCopyrightText: 2019-2023 Blender Foundation
   2 #
   3 # SPDX-License-Identifier: GPL-2.0-or-later
   4
   5
   6 # LOAD MODULE #
   7 import bpy
   8 from bpy import *
   9 from bpy.props import *
  10
  11 import blf
  12 import gpu
  13 from gpu_extras.batch import batch_for_shader
  14
  15 import math
  16 import mathutils
  17 from mathutils import Vector
  18 from mathutils.geometry import interpolate_bezier
  19
  20
  21 def get_points(spline, matrix_world):
  22
  23     bezier_points = spline.bezier_points
  24
  25     if len(bezier_points) < 2:
  26         return []
  27
  28     r = spline.resolution_u + 1
  29     if r < 2:
  30        return []
  31     segments = len(bezier_points)
  32
  33     if not spline.use_cyclic_u:
  34         segments -= 1
  35
  36     point_list = []
  37     for i in range(segments):
  38         inext = (i + 1) % len(bezier_points)
  39
  40         bezier_points1 = matrix_world @ bezier_points[i].co
  41         handle1 = matrix_world @ bezier_points[i].handle_right
  42         handle2 = matrix_world @ bezier_points[inext].handle_left
  43         bezier_points2 = matrix_world @ bezier_points[inext].co
  44
  45         bezier = bezier_points1, handle1, handle2, bezier_points2, r
  46         points = interpolate_bezier(*bezier)
  47         point_list.extend(points)
  48
  49     return point_list
  50
  51 def draw(self, context, splines, curve_vertcolor, matrix_world):
  52
  53     for spline in splines:
  54         points = get_points(spline, matrix_world)
  55
  56         shader = gpu.shader.from_builtin('UNIFORM_COLOR')
  57
  58         batch = batch_for_shader(shader, 'POINTS', {"pos": points})
  59
  60         shader.bind()
  61         shader.uniform_float("color", curve_vertcolor)
  62         batch.draw(shader)
  63
  64
  65 class ShowCurveResolution(bpy.types.Operator):
  66     bl_idname = "curvetools.show_resolution"
  67     bl_label = "Show Curve Resolution"
  68     bl_description = "Show curve Resolution / [ESC] - remove"
  69
  70     handlers = []
  71
  72     def modal(self, context, event):
  73         context.area.tag_redraw()
  74
  75         if event.type in {'ESC'}:
  76             for handler in self.handlers:
  77                 try:
  78                     bpy.types.SpaceView3D.draw_handler_remove(handler, 'WINDOW')
  79                 except:
  80                     pass
  81             for handler in self.handlers:
  82                 self.handlers.remove(handler)
  83             return {'CANCELLED'}
  84
  85         return {'PASS_THROUGH'}
  86
  87
  88     def invoke(self, context, event):
  89
  90         if context.area.type == 'VIEW_3D':
  91
  92             # color change in the panel
  93             curve_vertcolor = bpy.context.scene.curvetools.curve_vertcolor
  94
  95             splines = context.active_object.data.splines
  96             matrix_world = context.active_object.matrix_world
  97
  98             # the arguments we pass the the callback
  99             args = (self, context, splines, curve_vertcolor, matrix_world)
 100
 101             # Add the region OpenGL drawing callback
 102             # draw in view space with 'POST_VIEW' and 'PRE_VIEW'
 103             self.handlers.append(bpy.types.SpaceView3D.draw_handler_add(draw, args, 'WINDOW', 'POST_VIEW'))
 104
 105             context.window_manager.modal_handler_add(self)
 106             return {'RUNNING_MODAL'}
 107         else:
 108             self.report({'WARNING'},
 109             "View3D not found, cannot run operator")
 110             return {'CANCELLED'}
 111
 112     @classmethod
 113     def poll(cls, context):
 114         return (context.object is not None and
 115                 context.object.type == 'CURVE')
 116
 117 def register():
 118     for cls in classes:
 119         bpy.utils.register_class(operators)
 120
 121 def unregister():
 122     for cls in classes:
 123         bpy.utils.unregister_class(operators)
 124
 125 if __name__ == "__main__":
 126     register()
 127
 128 operators = [
 129     ShowCurveResolution,
 130     ]