How To Build An Equirectangular Sphere Mesh

Build a nice spheremesh with no distortion at the poles using Blender v2.91

#Unity3D  #Blender3D  #Equirectangular  #Virtual Reality  #tutorial  #planetarium  #DigitalArt  #Blender 2.91 

  • When you are representing equirectangular, also known as mercator, images and videos, you will need a mesh to show it on. This is how you build that mesh using Blender 2.91.

    Step By Step Instructions

    • select the cube with left click in 3D view
    • x, Enter deletes the cube
    • Shift S, 1 to center cursor in case it’s been moved
    • Make sure your mouse is over the 3D Window view
    • Shift A, m, g Enter Add > Mesh > Grid
    • Click the Drop Arrow on the Add Grid action indicator in the lower left corner
      • X subdivisions: set to 128
      • Y subdivisions: set to 72
      • Size should be left at 2
      • Generate UVs is checked
      • This will make a UV map that lines up to exact pixel locations for 16:9 widescreen presentations on a cube map, reducing the amount of blurring caused by uv map distortion compared to non optimized ratios.

    Add test texture to the grid

    • With Grid selected
    • Click on the Material tab in a Properties Pane
    • Click New
    • Go to the Base Color setting, click on the yellow dot Set to Image/Texture
    • Set your equirectangular test texture
    • Linear, Flat, Clip, Single Image
    • Switch On material viewport shading in the 3D window
      • You may have to zoom in a little to see the texture, do this by rolling the mouse scrollwheel, or de-pincering if you’re a brave Blender user on a touchpad

    Warp The Mesh

    • Num Pad 5 Ortho View
    • With the new grid selected
    • Tab to set edit mode, don’t miss this step!
    • a Select All
    • s, x, -1, Enter Scale on x axis to reverse
    • Num Pad 3 for Ortho Right View
    • g, z, 1, Enter to translate up 1 scene unit
    • F3 To Search - Type Warp - or - Click on Mesh - Transform - Warp
    • Click on the Warp values window in the lower left corner
    • Warp Angle should be 180
    • Move the mouse cursor back over the grid
    • Num Pad 1 for Front Ortho view
    • F3 to Search should bring up the previous Warp action - or - Click on Mesh - Transform - Warp
    • This time, set the warp angle to 360
    • Num Pad 3 to go to Right View
    • r, 90, Enter Rotates the sphere so the views line up with the axes
    • Tab to exit edit mode and get back into object mode
    • Add a triangulate modifier with the modifier window (if you want to use a triangulated mesh)
    • F3 to open search type “export obj” and select the wavefront export option
    • Check the “Selected Objects Only” box
    • If you plan on using the mesh in Unity, you should set
      • Up Y+
      • Forward Z-

    Using Your Equirectangular Sphere in Unity3D:

    • You can now use the mesh to display your equirectangular content.
    • You should set any material textures to clamp, not repeat
    • The more ansio (anisotropic filtering) the better (6+ in Unity)