Blender tips

Used Blender version 4 to place cameras in scenes.

Position camera

• Place world viewport in the desired position to place a camera.

• Press ctrl + alt + numpad 0 to place a new camera.

• Check the world coordinates of the camera in Object Properties of the placed camera.

• Move camera to the desired point to look at, and check wich coordinates are changed,

  • By doing this, the lookAt can be infered from the difference of both positions (before and after).

How to convert Axis from Blender (default) to MobileRT:

Axis in Blender (default)	Axis in MobileRT
X	-X (Loader automatically converts to -X)
Y	-Z
Z	Y

Check Blender documentation.

Create camera file

E.g. of camera for San Miguel scene:

t perspective
p 20.0 1.0 5.0
l 19.0 1.0 5.0
u 0.0 1.0 0.0
f 45 45

Place single world light

• Select Edit Mode in Layout menu.

• Create a plan composed by 2 triangles.

  • Do not select other object to avoid merge 2 primitives into 1.

  • Provide X, Y and Z coordinates.

  • Provide size to scale it and cover the desired scene.

  • Place it above the scene and make it face the scene.

  • Enable Face Orientation in Viewport Overlay menu to know where primitives are facing.

    • Blue is front side and red is back side.

• Export the scene into a new Wavefront OBJ file.

E.g. of world light position for San Miguel scene:

o PlaneMobileRT
v 5000 20 5000
v -5000 20 5000
v 5000 20 -5000
v -5000 20 -5000
vn 0 -1 0
vt 0 0
vt 1 0
vt 1 1
vt 0 1
s 0
usemtl LightMobileRT
f 5933232/2220965/9754200 5933233/2220966/9754200 5933235/2220967/9754200 5933234/2220968/9754200

And the material:

newmtl LightMobileRT
Ns 250
Ka 1 1 1
Kd 0.8 0.8 0.8
Ks 0.5 0.5 0.5
Ke 1 1 1
Ni 1.45
d 1
illum 2