PNG alpha channel transparency not working

Rhino WIP 7.0.20203.15405, 21.07.2020

System info

Rhino 7 SR0 2020-7-21 (Public Build, 7.0.20203.15405, Git hash:master @ 58c6ed1fec2f18dc6f0a87be0ee7238d65606456)
License type: Edukacyjna, build 2020-07-21
License details: Cloud Zoo
Expires on: 2020-09-04

Windows 10.0 SR0.0 or greater (Physical RAM: 32Gb)

Non-hybrid graphics.
Primary display and OpenGL: NVIDIA GeForce GTX 1070 (NVidia) Memory: 8GB, Driver date: 6-21-2020 (M-D-Y). OpenGL Ver: 4.6.0 NVIDIA 451.48

OpenGL Settings
Safe mode: Off
Use accelerated hardware modes: On
Redraw scene when viewports are exposed: On

Anti-alias mode: 4x
Mip Map Filtering: Linear
Anisotropic Filtering Mode: Height

Vendor Name: NVIDIA Corporation
Render version: 4.6
Shading Language: 4.60 NVIDIA
Driver Date: 6-21-2020
Driver Version:
Maximum Texture size: 32768 x 32768
Z-Buffer depth: 24 bits
Maximum Viewport size: 32768 x 32768
Total Video Memory: 8 GB

Rhino plugins that do not ship with Rhino

Rhino plugins that ship with Rhino
C:\Program Files\Rhino WIP\Plug-ins\Commands.rhp “Commands” 7.0.20203.15405
C:\Program Files\Rhino WIP\Plug-ins\WebBrowser.rhp “WebBrowser”
C:\Program Files\Rhino WIP\Plug-ins\rdk.rhp “Renderer Development Kit”
C:\Program Files\Rhino WIP\Plug-ins\RhinoScript.rhp “RhinoScript”
C:\Program Files\Rhino WIP\Plug-ins\IdleProcessor.rhp “IdleProcessor”
C:\Program Files\Rhino WIP\Plug-ins\RhinoRenderCycles.rhp “Rhino Render” 7.0.20203.15405
C:\Program Files\Rhino WIP\Plug-ins\rdk_etoui.rhp “RDK_EtoUI” 7.0.20203.15405
C:\Program Files\Rhino WIP\Plug-ins\rdk_ui.rhp “Renderer Development Kit UI”
C:\Program Files\Rhino WIP\Plug-ins\NamedSnapshots.rhp “Snapshots”
C:\Program Files\Rhino WIP\Plug-ins\Alerter.rhp “Alerter”
C:\Program Files\Rhino WIP\Plug-ins\RhinoCycles.rhp “RhinoCycles” 7.0.20203.15405
C:\Program Files\Rhino WIP\Plug-ins\Toolbars\Toolbars.rhp “Toolbars” 7.0.20203.15405
C:\Program Files\Rhino WIP\Plug-ins\3dxrhino.rhp “3Dconnexion 3D Mouse”
C:\Program Files\Rhino WIP\Plug-ins\Displacement.rhp “Displacement”

PNG alpha channel transparency is not working. I think that two builds ago it was working. Maybe by coincidence but I noticed it stopped working after @andy made some changes discussed in the thread Refreshing Textures got slower & annoying - #12 by brian

Can anyone confirm that?

I noticed that 8-bit PNG texture files looks like they have almost inverted colors or are completely black. The same texture files opened in the Photoshop or Windows look correctly.

8 bit png file:

32 bit png file:

test file: rhino png test.3dm (203.6 KB)

I can duplicate that.
V6 is okay, V7 is not.


RH-59602 is fixed in the latest WIP

Thank you for looking into this problem.

The problem seems to be fixed at the first glance, but there are still some issues.

Transparency is ignored when it comes to casting/not casting shadows.

Rhino 6:

Rhino WIP:

New bug:

1 Like

I’m having trouble repeating this new issue.
How does this file look on your system in V6 and V7?
rhino png test V6.3dm (246.0 KB)

Make sure your “Rendered” working display mode is set to defaults

It looks that it was my fault, my presumptions based on the previous bug was wrong. Sorry for the false report.

I was experimenting with the view modes and didn’t realize that I set transparent objects to always cast shadows.

I have cancelled that second defect report.