Results 1 to 5 of 5

Thread: vkCmdBlitImage w/ alpha

  1. #1
    Junior Member
    Join Date
    Nov 2017
    Posts
    3

    Angry vkCmdBlitImage w/ alpha

    Is there a way to use vkCmdBlitImage, or a similar function, while taking into account the image's alpha channel?

  2. #2
    Back in the day, hardware used to have blit operations that cared about "transparent pixels". But that day was a long time ago. And even then, "transparent pixels" were almost never alpha channels; they were a color key, a specific color designated to mean "transparent".

    When you want to do the kind of thing you're wanting to do nowadays, we call that "rendering". You just render a quad of the appropriate size in the appropriate location, using a shader that accesses the appropriate texture, with an appropriate blending mode.

  3. #3
    Junior Member
    Join Date
    Nov 2017
    Posts
    3
    I see. So it's impossible to draw a texture directly to screen while taking into account the alpha channel. Is it possible to do so without a vertex shader though?
    I new to both Vulkan and OpenGL so I apologize if any of these questions are stupid; I'm pretty sure they are :P

  4. #4
    Is it possible to do so without a vertex shader though?
    No. You need to use a rendering operation, and all rendering operations require a vertex shader. I don't know why that's such an onerous burden, since you also need to set up the rest of the rendering pipeline, as well as vertex buffers and the like.

  5. #5
    Junior Member
    Join Date
    Nov 2017
    Posts
    3
    Quote Originally Posted by Alfonse Reinheart View Post
    I don't know why that's such an onerous burden, since you also need to set up the rest of the rendering pipeline, as well as vertex buffers and the like.
    It really isn't actually. Thank you

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Proudly hosted by Digital Ocean