blender, python, 球の動作


blender, python, 球の動作
blender 2.8, python, の記事。続きです。今日やったのは立方体の配置、照明配置カメラ配置、着色。キーフレーム指定での球の動きと円柱の動き。球の着色に少し手間取りました。R,G,B,alphaと4つ数値を並べるのがわかるようでわからないまま。
twitterに1秒間の動画[blender 2.8, python.  動画1秒, 33kB](https://twitter.com/naohiko7/status/1295727667661037568) を投稿しています。画質は400px*300pxで荒いまま。
![qiita_s20200818.png](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/690216/465ee2a6-84dc-bd92-7da1-f77ad9ec7b20.png)


```python3
import bpy
# nh06 ( キーフレーム応用で 円筒形と球形を動かす）

# 既存 mesh, light, camera, みな削除
for item in bpy.data.objects:
	bpy.data.objects.remove(item)

#立方体 original script は  ---- http://tips.hecomi.com/entry/20120818/1345307205

START = 0
END   = 100
N     = 3

# Add color cubes
for x in range(0, N):
    for y in range(0, N):
        for z in range(0, N):
            # Add a color cube
            bpy.ops.mesh.primitive_cube_add( location=(x*3, y*3, z*3) )
            #obj = bpy.context.scene.objects.active #(old blender2.7script)
            obj = bpy.context.view_layer.objects.active
            #mat.diffuse_color = (x/N, y/N, z/N)#(old blender2.7script)
            mat = bpy.data.materials.new('Cube')
            mat.diffuse_color = (x/N, y/N, z/N, 0)
            #mat.use_transparency = True #(この行は2.8で試していない)
            #mat.alpha = 0.6 #(この行は2.8で試していない)
            obj.data.materials.append(mat)


# new camera
bpy.ops.object.add(radius=1.0, type='CAMERA', enter_editmode=False, align='WORLD', location=(20.0, -6.0, 8.0), rotation=(1.4, 0.0, 1.2))

# new lamps （出典 stack overflow Can you add a light source in blender using python)
# create light datablock, set attributes
light_data = bpy.data.lights.new(name="light_2.80", type='POINT')
light_data.energy = 3000
# create new object with our light datablock
light_object = bpy.data.objects.new(name="light_2.80", object_data=light_data)
# link light object
bpy.context.collection.objects.link(light_object)
# make it active 
bpy.context.view_layer.objects.active = light_object
#change location
light_object.location = (5, -4, 10)
# update scene, if needed
dg = bpy.context.evaluated_depsgraph_get() 
dg.update()

# 背景 world - surface - background
bpy.data.worlds["World"].node_tree.nodes["Background"].inputs[0].default_value = (0.01, 0.15, 0.25, 1)
bpy.data.worlds["World"].node_tree.nodes["Background"].inputs[1].default_value = 0.7            
#=====

# ================
# cylinder 動かす ( nh02 動きの応用)
bpy.context.scene.frame_start = 1
bpy.context.scene.frame_end = 30
bpy.context.scene.frame_current = 10
# MOVE Cylinder mesh with KEY FRAME 
bpy.ops.mesh.primitive_cylinder_add(rotation=(-0.8, 0.0, 0.0))
bpy.context.scene.frame_current = 1 # set frame to 1
cdnow  = bpy.context.object          # get new object just created
cdnow.location = (1,-1,1) # set the location
bpy.ops.anim.keyframe_insert_menu(type='Location') # KEY FRAME
bpy.context.scene.frame_current = 10 # set frame to 10
cdnow.location = (1,7,7)
bpy.ops.anim.keyframe_insert_menu(type='Location') # KEY FRAME
bpy.context.scene.frame_current = 20 # set frame to 20
cdnow.location = (8,6,3)
bpy.ops.anim.keyframe_insert_menu(type='Location') # KEY FRAME
bpy.context.scene.frame_current = 30 # set frame to 30
cdnow.location = (1,-1,1)
bpy.ops.anim.keyframe_insert_menu(type='Location') # KEY FRAME
#  ==================


# MOVE UV Sphere mesh with KEY FRAME (# Add UV Sphere)
bpy.ops.mesh.primitive_uv_sphere_add (segments=32, ring_count=16, radius=1.0, calc_uvs=True, enter_editmode=False, align='WORLD', location=(4.0, -2.0, 6.0), rotation=(0.0, 0.0, 0.0))

mat = bpy.data.materials.new('Sphere')
obj = bpy.context.view_layer.objects.active
mat.diffuse_color = (0.8, 0.8, 0.1, 0.4)  # sphere color (R,G,B,Alpha)
obj.data.materials.append(mat)

bpy.context.scene.frame_current = 1 # set frame to 1
cdnow  = bpy.context.object    # get new object just created
cdnow.location = (4.0, -2.0, 6.0) # set the location
bpy.ops.anim.keyframe_insert_menu(type='Location') # KEY FRAME
bpy.context.scene.frame_current = 15 # set frame to 15
cdnow.location = (4.0, 1.0, 7.0)
bpy.ops.anim.keyframe_insert_menu(type='Location') # KEY FRAME
bpy.context.scene.frame_current = 22 # set frame to 22
cdnow.location = (4,3,4)
bpy.ops.anim.keyframe_insert_menu(type='Location') # KEY FRAME
bpy.context.scene.frame_current = 30 # set frame to 30
cdnow.location = (4.0, -2.0, 6.0)
bpy.ops.anim.keyframe_insert_menu(type='Location') # KEY FRAME
#  ==================

```