**System Information**
win8.1 pro 64bit, nvidia gt650M 2gb
**Blender Version**
Broken: 2.71.6 d919218
Worked: na
**Short description of error**
The cycles image texture node gives unexpected results with png alpha channels (alpha set to zero but color channel is non-zero) in rendered 3D view.
**Exact steps for others to reproduce the error**
Say you have a png image with alpha set to 0 at some places, but where color is non-zero.
Plug the Color output of image texture to emission node.
Checking/unchecking the "Use Alpha" property in the image texture properties panel should update the 3D rendered view and show or not show color when alpha is zero.
Packed images are updated in 3D view as expected, but non-packed images aren't.
On the uploaded file:
png file is shown with alpha and color channels on the lower half.
(png image is packed)
- set 3D view to rendered mode
- uncheck/check "Use Alpha" in Image Texture properties
- 3D rendered view is updated as expected (F12 render is updated expectedly as well)
- unpack the image texture
(png image is not packed)
- check/uncheck "Use Alpha" in Image Texture properties
- 3D rendered view is not updated as expected (although F12 render is updated expectedly)
{F111847}