Blender for Generating Images

Install Blender

If you are a Linux user, installation is super easy.
(1) Open the Ubuntu Software, or click that icon on your menu bar
(2) Find the ‘Blender’
(3) Install the ‘Blender’

Control

Tab: Switch edit mode to object mode, vice versa

Shift + a: Add almost everything
Shift + d, Alt + d: Copy and paste
Shift + z: Change the viewport of the object Shift + s: Utility about cursor&mouse, i.e., cursor to world origin

Ctrl + R: Cut roop Ctrl + b: Bevel, can soften the edge of the object

. : Focus on the selected object
Delete: Delete z: Render mode W: Smooth and flat, and some more utilities
G: Move the object
G + x or y or z: Move the object on the axis, x or y or z
S: Scale up or scale down
S + x or y or z: Scaling the object on the axis, x or y or z
R: Rotate the object
R + x or y or z: Rotating on the axis, x or y or z
M: Collect the selected several objects into one object

F3: Search and use the utility

Control + z: Undo

Left click + R: Rotate
Left click + G: Move
Left click + S: Scale up or scale down
Left click + Shift + Left Click: Group
Drag using left click: Group

Mouse wheel: Change the view position (fixed object)
Shift + Mouse wheel: Move the view position (not fixed object)
Up-scrolling wheel: Increase the size of view
Down-scrolling wheel: Decrease the the size of view

Color

(1) Right Click on the target object
(2) Click the Material Properties
(3) Click the Use Nodes in the Blue button
(4) Select the Base Color, and Change the Color

also refer to shading tab.

Light

(1) Right Clcik on the Light
(2) Click the Object Data Properties
(3) Change the Color, Power and Radius

• If you place the light too far from your object or make it so weak,
  there might be no light effect.

Video

Space Bar: Play
Shift + Left Key: Go back to the first
Shift + Right Key: Go to the last

Multiple images using multiple cameras

(1) Make some new cameras
(2) Check each camera view
(3) Go to output properties
(4) Check stereoscopy, multi-view and then individual in views format
(5) Synchronize the suffix and camera name in multi-view utility
(6) Press F12 and save the images

Numpad 1, 3, 7, 9: They are control key for seeing differently in XYZ cartesian coordinate system.
Numpad 0: View of camera

Viewport

There are four viewport options you can change,
Wireframe, Solid, Material and Rendered.

Render

Eevee: Fast and cheap. You should use some options like as ambient occlusion, screen space reflections…
Cycles: Slow and expensive, but the quality is super excellent.

Fog

In shading mode > Go to world environment > Shift + A, Shader, princial volume > Connect

Shading and Rendering

These are really so interesting and great.
Click the Shading on Tool bar, You can choose the Rendering mode.
Click the target object and press the new button,
you can change and control the object properties.

LoopTools

You can use the loopTools utility with W key.
Turn on that tool.
Edit > Preferences > Add-ons > search: loop top > Activate to Mesh: LoopTools

Useful tips

Setting HDRI (High Dynamic Range Imaging) background

(1) Downlaod the hdri image at https://hdrihaven.com/
(2) In Shading place, change the World.
Shift+A > Texture > Environment Texture > Open that hdri image > Connect

Make a hole in Mesh

(1) Make a Object to get a hole
(2) Make a Cutting object like as cyliner, circle
(3) Click the (1), Add Modifier > Boolean in Generate > Set Operation to Difference > Click the Spoide in Object Section
(4) Click the Cylinder
(5) Apply

Fix Scale

(1) Adjust the dimensions of object
(2) It’s size will be changed and scale also
(3) Click the obejct and then Ctrl + A > Scale.
(4) It is going to be 1.0 of scale.

Select Box

If the select box disapeared
(1) Check that icon above the Cursor
(2) Click and Drag to right bottom side
(3) Choose the Select Box

Move all the object together

It is Proportional Editing Objects mode.
You have to turn off the PEO mode, press the key, O.

Activate that, To Sphere

To activate that ‘to sphere’ utility,
Shift + Alt + S.

Pink screen or Insane screen suddenly comes up while rendering

Check that path of HDR file is correct or not.

Round edges

(1) Select the object
(2) Go to Edit mode then edges or 2
(3) Click the Edges
(4) Let’s do that bevel
(5) Move the Whell-scroll of the mouse

If Boolean makes some problems?

I think it always makes problems.
If the hole maker which is cylinder or something is on the edges of object,
it cause problems.
Maybe you can’t select the object or there is no boolean effect. (1) Generate a new object to cut hole or to be cutted.
(2) Change the sequence of cutting hole.
(3) Re-try from the start until there.

Subdivide, it can be able to solution sometimes.
Before doing Boolean, do subdvide firstly.

Merge or Join some objects

(1) Click the first object
(2) Click another object that you want to make into one
(3) Ctrl + J

Smooth Faces

(1) Go to Edit mode
(2) Select all the faces need to be changed
(3) Mesh menu (on the upper-left side) > Shading > Smooth Faces

Render Animation

You can choose the type of file, jpg, png or avi.
(1) At the first frame, press I key and save the location of object.
(2) Some frames later, change the location of object and save it with I button.
(3) Repeat the processes until end of the frame.

Focal length & Sensor Fit, Sensor Size

If you want to make it much more closer compared with the image of real object,
You have to consider about some parameters.
And Focal length and Sensor information are very important.
You can check your camera & sensor out, then change the values.
(1) Select the camera what you want to change
(2) Go to object Data Properties tab
(3) Change the values of Focal Length, Sensor Size.

Export as file type ‘.obj’

There are some options to save the object as like ‘.obj’ file type.
If you want to export it as an one object which is consist of several parts,
click the Objects as OBJ Groups, path: copy.
Otherwise, just save it with Objects as OBJ Objects.

Import ‘.obj’ file with having material issue

If you made an object using nodes about the texture&surface,
it can be an issue.
So you have to make a material without nodes,
and export it.
Don’t click the ‘Use Nodes’, and at the material properties,
just use the Viewport Display like as Color, Metallic and Roughness.
When you export the object, set the ‘Path Mode’: ‘Copy’

When the object is disappeared with increasing the camera view or change the parameter

Set the value of ‘clip start’ and ‘clip end’ as much as the size of your object.
0.1 ~ 10 or 0.1 ~ 100.