Blender Materials: Light Emission

Introduction

An animated scene uses light to influence how the objects are viewed and how visible they are. Blender provides various options for lights. To start, when you start a project, Blender adds a default light. You can keep it, change it, delete it, or replace it.

Practical Learning: Introducing the Project

1. Start Blender
2. In the Properties window, click the Object button

Practical Learning: Modeling a Room

1. In the Tools window, click the Create tab
2. In the Create tab of the Tools window, click Plane
3. To change the name of the shape, in the Properties window, click Plane to select the name
4. Type Back Wall and press Enter
5. In the Transform section, change the following values:

   Location - Y:  8
              Z:  5
   Rotation - X: 90
   Scale    - X: 8
              Y: 5

6. To add a new plane, in the Create tab of the Tools window, click Plane
7. While the plane is still selected, in the Properties window, change the following values:

   Name       Left Wall
   Location - X: -8
              Z:  5
   Rotation - Y: 90
   Scale    - X: 5
              Y: 8

8. To add a new plane, on the menu below the work area, click Add -> Mesh -> Plane
9. While the plane is still selected, in the Properties window, change the following values

   Name:      Floor
   Location - Z: .01
   Scale    - X: 11
              Y: 11

10. Zoom in to get a better view of the scene. Here is an example:

    

Practical Learning: Modeling a Ceiling Fan

1. Position the mouse in the work area and press Shift + A -> Mesh -> Cylinder
2. In the Add Cylinder section below the Tools window, change the following values

   Vertices:  8
   Radius:   .065
   Depth:     6
   Location - Z: 8.5

   

3. On the menu bar of the 3D View, click Add -> Mesh -> UV Sphere
4. In the Add UV Sphere section below the Tools window, change the following values:

   Size:     .5
   Location - Z: 5.5

5. While the sphere is selected, position the mouse in the work area, press M and, in the Layers window, click the second box
6. On the menu bar of the 3D View, in the Visible Layers section, click the second button
7. Zoom in to see as much as possible of the sphere
8. In the Numeric Pad of the keyboard, press 1 to access the front view
9. Press 5 to display the sphere in orthographic view
10. Press Tab to display in Edit Mode

11. Press Z to display in Wireframe mode
12. Press A to deselect everything
13. Press B to prepare to box-select
14. Draw a rectangle that selects the top lines excluding the middle line and the line just above it:

    

    

15. Press X
16. In the menu that appears, click Faces:

    

17. Zoom out to see less of the sphere
18. Press Tab to display the Object Mode
19. In the Numeric Pad, press 5 to return to the perspective view
20. Press Z to return to the Solid view
21. In the Properties window, change the name to Ceiling Light and press Enter
22. In the Tools window, click the Tools tab and click Smooth
23. While the object is selected, position the mouse in the work area, press M and, in the Layers window, click the first box
24. In the Tools window, click the Create tab
25. In the Tools window, click Cylinder
26. In the Add Cylinder section below the Tools window, change the following values

    Vertices:   5
    Radius:    .65
    Depth:     .25
    Location - Z: 5.65

27. In the Object section of the Properties window, change the name to Ceiling Fan and press Enter
28. Zoom in to see as much as possible of the hexagon:

    

29. Press Tab to display in Edit Mode
30. On the menu bar of the 3D-View, click the Face Select button
31. Right-click one of the vertical faces to select it
32. Press I to create an inset on the selected face
33. Type .05 and press Enter:

    

34. Using the same technique, create an inset on each vertical face:

    

35. By pressing and holding Shift while right-clicking, select each of the inside faces you had created to select all of them:

    

    

36. On the menu bar of the 3D View, click the Pivot button and select Individual Origins:

    

37. Zoom out to display the hexagon far from you
38. Press E to extrude
39. Type 1.5

    

40. Press Enter
41. While the faces are still selected, press S to change their sizes
42. Type .75 and press Enter:

    

43. Press R to rotate
44. Type -30 and press Enter:

    

45. On the menu bar of the 3D View, click the Pivot button and select Median Point
46. Press Tab to return to the Object Mode
47. Zoom out to see less of the ceiling fan
48. Press M and, in the Layers window, click the first button
49. On the menu bar of the 3D View, in the Visible Layers section, click the first button:

    

Practical Learning: Creating the Lights

1. In the Tools window, click the Create tab and click Plane
2. In the Properties window, change the following values

   Name:      Local Light
   Location - X: -4
              Y: -4
              Z:  10
   Rotation - X: 30
              Y: -35
   Scale    - X: 2
              Y: 1.5

3. In the Tools window, click the Create tab if necessary and click Plane
4. In the Properties window, change the following values

   Name:      Projected Light
   Location - X:   6
              Y:   4
              Z:   10
   Rotation - X: -20
              Y:  45
   Scale    - X:   2.5
              Y:   3.5

   

5. Position the mouse in the work area and, to display the camera view, in the Numeric Pad, press 0
6. Press N to display the Properties Region
7. In the Properties Region, click the Lock Camera to View check box
8. Use the mouse and the keyboard to position the view so you can see the whole area. Here is an example:

   

9. In the Properties Region, click Lock Camera to View to uncheck it
10. Press N to close the Properties Region
11. To preview the result, on the top menu, click Render -> Render Image
12. After viewing the result, press Esc to return to the 3D View

Creating a Custom Light

To get a custom light, create a shape such as a plane or else. Then apply a shader named Emission to it.

In this exercise, we will ignore or remove the existing lamp (we could have kept it) and use only custom lights to the scene.

Practical Learning: Creating Some Lights

1. In the top menu bar, click Blender Render and select Cycles Render
2. On the menu bar of the 3D View, click the Viewport Shading button and select Material:

   

3. In the Properties window, click the Render button
4. In the Properties window, in the Resolution section, click 50%, type 100 and press Enter
5. Click Sampling to expand it
6. In the Samples section, set the Render value to 500
7. On the scene, right-click the existing light to select it
8. Press X to delete
9. In the menu that appears, click Delete
10. In the Outliner, click Local Light to select it
11. In the Properties window, click the Material button
12. In the Material section of the Properties window, click New
13. In the Surface text box, click Diffuse BSDF and, in the menu that appears, click Emission:

    

14. Change the Strength value to 5 and press Enter
15. Click the Color button and select a light-yellow color (I am using R = 0.800, G = 0.800, and B = 0.45):

    

16. Right-click the bottom border of the top menu bar and click Split Area:

    

17. Position the mouse somewhere between the middle of the work area and the right border
18. Click to confirm. If necessary, resize the windows
19. In the bottom-left side of the new window, click the 3D Viewport button and select Node Editor

    n

20. Position the mouse inside the new window and press N to close its Properties Region
21. Zoom in the Node Editor to get a larger view of its content
22. In the Outliner, click Ceiling Light
23. On the menu bar of the Node Editor, click New
24. In the Properties window, click Diffuse BSDF and, in the menu that appears, click Emission
25. In the Node Editor, in the Emission box, change the Strength to 8 and press Enter
26. In the Outliner, click Projected Light
27. In the Properties window, click the New Button
28. In the Node Editor, click the body of Diffuse to select it:

    

29. Press Delete
30. On the menu bar of the Node Editor, click Add, position the mouse on Shader, and click Emission:

    

31. Position the Emission window to the left of the Output window
32. Drag the green button from the Emission window and drop it the green button of Surface in the Material Output window
33. In the Emission window, change the Strength to 10

    

34. Right-click the line between the 3D Viewport and the Node Editor
35. In the menu that appears, click Join Area:

    

36. Position the mouse in the Node Editor and click (or click the right-pointing arrow)
37. In the Properties window, click the Render button
38. To preview the result, in the Render section, click the Render button

    

39. After viewing the result, press Esc to close the render view
40. In the Outliner, click Floor
41. In the Properties window, click the Material button if necessary
    In the Material section of the Properties window, click the New button
42. Click the Preview button to expand it
43. Click the Color button
44. Set the RGB color as:

    R: .515
    G: .515
    B: .515

45. In the Outliner, click Ceiling Fan
46. In the Material section of the Properties window, click the New Button
47. In the Properties window, click the Color button
48. Click its Hex button and set the color as 3D0C02
49. In the work area, right-click the tiny long cylinder above the ceiling fan
50. In the Material section of the Properties window, click the New button
51. Click the Color button and click RGB
52. Set the color value as follows:

    R: .025
    G: .005
    B: .005

53. In the work area, right-click the wall on the left side (alternatively, in the Outliner, click Left Wall) to select it
54. In the Material section of the Properties window, click the New button
55. Click the Color button and set the Hex value to 3366CC
56. In the work area, click the right wall (alternatively, in the Outliner, click Back Wall)
57. In the Material section of the Properties window, click the New button
58. Click Color and set the Hex value to 3399FF and press Enter
59. In the work area, right-click the tiny cylinder above the lamp to select it
60. In the Properties window, click New and click Color
61. Set the Hex value as 3D0C02 and press Enter
62. In the Properties window, click the Render button
63. To preview the result, in the Render section, click the Render button

    

64. After viewing the result, press Esc to close the render vieW