sun_position/draw.py

   1 # SPDX-FileCopyrightText: 2019-2023 Blender Foundation
   2 #
   3 # SPDX-License-Identifier: GPL-2.0-or-later
   4
   5 import bpy
   6 import math
   7 import gpu
   8 from gpu_extras.batch import batch_for_shader
   9 from mathutils import Vector
  10
  11 from .sun_calc import calc_surface, calc_analemma
  12
  13
  14 if bpy.app.background:  # ignore drawing in background mode
  15     def north_update(self, context):
  16         pass
  17     def surface_update(self, context):
  18         pass
  19     def analemmas_update(self, context):
  20         pass
  21 else:
  22     # North line
  23
  24     shader_interface = gpu.types.GPUStageInterfaceInfo("my_interface")
  25     shader_interface.flat('VEC2', "v_StartPos")
  26     shader_interface.smooth('VEC4', "v_VertPos")
  27
  28     shader_info = gpu.types.GPUShaderCreateInfo()
  29     shader_info.push_constant('MAT4', "u_ViewProjectionMatrix")
  30     shader_info.push_constant('VEC4', "u_Color")
  31     shader_info.push_constant('VEC2', "u_Resolution")
  32     shader_info.vertex_in(0, 'VEC3', "position")
  33     shader_info.vertex_out(shader_interface)
  34
  35     shader_info.vertex_source(
  36         '''
  37         void main()
  38         {
  39             vec4 pos    = u_ViewProjectionMatrix * vec4(position, 1.0f);
  40             gl_Position = pos;
  41             v_StartPos    = (pos / pos.w).xy;
  42             v_VertPos     = pos;
  43         }
  44         '''
  45     )
  46
  47     shader_info.fragment_out(0, 'VEC4', "FragColor")
  48     shader_info.fragment_source(
  49         '''
  50         void main()
  51         {
  52             vec4 vertPos_2d = v_VertPos / v_VertPos.w;
  53             vec2 dir  = (vertPos_2d.xy - v_StartPos.xy) * u_Resolution;
  54             float dist = length(dir);
  55
  56             if (step(sin(dist / 5.0f), 0.0) == 1) discard;
  57
  58             FragColor = u_Color;
  59         }
  60         '''
  61     )
  62
  63     shader = gpu.shader.create_from_info(shader_info)
  64     del shader_info
  65     del shader_interface
  66
  67     def north_draw():
  68         """
  69         Set up the compass needle using the current north offset angle
  70         less 90 degrees.  This forces the unit circle to begin at the
  71         12 O'clock instead of 3 O'clock position.
  72         """
  73         sun_props = bpy.context.scene.sun_pos_properties
  74
  75         color = (0.2, 0.6, 1.0, 0.7)
  76         radius = 100
  77         angle = -(sun_props.north_offset - math.pi / 2)
  78         x = math.cos(angle) * radius
  79         y = math.sin(angle) * radius
  80         coords = Vector((x, y, 0)), Vector((0, 0, 0))
  81         batch = batch_for_shader(shader, 'LINE_STRIP', {"position": coords})
  82
  83         matrix = bpy.context.region_data.perspective_matrix
  84         shader.uniform_float("u_ViewProjectionMatrix", matrix)
  85         shader.uniform_float("u_Resolution", (bpy.context.region.width,
  86                                               bpy.context.region.height))
  87         shader.uniform_float("u_Color", color)
  88         width = gpu.state.line_width_get()
  89         gpu.state.line_width_set(2.0)
  90         batch.draw(shader)
  91         gpu.state.line_width_set(width)
  92
  93     _north_handle = None
  94
  95     def north_update(self, context):
  96         global _north_handle
  97         sun_props = context.scene.sun_pos_properties
  98         addon_prefs = context.preferences.addons[__package__].preferences
  99
 100         if addon_prefs.show_overlays and sun_props.show_north:
 101             if _north_handle is None:
 102                 _north_handle = bpy.types.SpaceView3D.draw_handler_add(north_draw, (), 'WINDOW', 'POST_VIEW')
 103         elif _north_handle is not None:
 104             bpy.types.SpaceView3D.draw_handler_remove(_north_handle, 'WINDOW')
 105             _north_handle = None
 106
 107     # Analemmas
 108
 109     def analemmas_draw(batch, shader):
 110         shader.uniform_float("color", (1, 0, 0, 1))
 111         batch.draw(shader)
 112
 113     _analemmas_handle = None
 114
 115     def analemmas_update(self, context):
 116         global _analemmas_handle
 117         sun_props = context.scene.sun_pos_properties
 118         addon_prefs = context.preferences.addons[__package__].preferences
 119
 120         if addon_prefs.show_overlays and sun_props.show_analemmas:
 121             coords = []
 122             indices = []
 123             coord_offset = 0
 124             for h in range(24):
 125                 analemma_verts = calc_analemma(context, h)
 126                 coords.extend(analemma_verts)
 127                 for i in range(len(analemma_verts) - 1):
 128                     indices.append((coord_offset + i,
 129                                     coord_offset + i+1))
 130                 coord_offset += len(analemma_verts)
 131
 132             shader = gpu.shader.from_builtin('UNIFORM_COLOR')
 133             batch = batch_for_shader(shader, 'LINES',
 134                                     {"pos": coords}, indices=indices)
 135
 136             if _analemmas_handle is not None:
 137                 bpy.types.SpaceView3D.draw_handler_remove(_analemmas_handle, 'WINDOW')
 138             _analemmas_handle = bpy.types.SpaceView3D.draw_handler_add(
 139                 analemmas_draw, (batch, shader), 'WINDOW', 'POST_VIEW')
 140         elif _analemmas_handle is not None:
 141             bpy.types.SpaceView3D.draw_handler_remove(_analemmas_handle, 'WINDOW')
 142             _analemmas_handle = None
 143
 144     # Surface
 145
 146     def surface_draw(batch, shader):
 147         blend = gpu.state.blend_get()
 148         gpu.state.blend_set("ALPHA")
 149         shader.uniform_float("color", (.8, .6, 0, 0.2))
 150         batch.draw(shader)
 151         gpu.state.blend_set(blend)
 152
 153     _surface_handle = None
 154
 155     def surface_update(self, context):
 156         global _surface_handle
 157         sun_props = context.scene.sun_pos_properties
 158         addon_prefs = context.preferences.addons[__package__].preferences
 159
 160         if addon_prefs.show_overlays and sun_props.show_surface:
 161             coords = calc_surface(context)
 162             shader = gpu.shader.from_builtin('UNIFORM_COLOR')
 163             batch = batch_for_shader(shader, 'TRIS', {"pos": coords})
 164
 165             if _surface_handle is not None:
 166                 bpy.types.SpaceView3D.draw_handler_remove(_surface_handle, 'WINDOW')
 167             _surface_handle = bpy.types.SpaceView3D.draw_handler_add(
 168                 surface_draw, (batch, shader), 'WINDOW', 'POST_VIEW')
 169         elif _surface_handle is not None:
 170             bpy.types.SpaceView3D.draw_handler_remove(_surface_handle, 'WINDOW')
 171             _surface_handle = None