Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
I have set up a quick 2D rendering system using OpenTK and OpenGL for a game.
I have set up transparency using:
GL.Enable(EnableCaps.Blend);
GL.BlendFunc(BlendingFactorSrc.One, BlendingFactorDest.OneMinusSrcAlpha);
However, whenever I go to draw (the texture is a png file loaded with System.Drawing), it only blends with the color I clear at the start of the draw call:
I just ended up switching to MonoGame, as it’s 2D rendering has already been sufficiently tested
Looks like you’re not drawing in the proper order. To get correct blending, you need to sort your polygons from back to front, so that anything ‘behind’ gets drawn first.
Based on that picture though, you might be better served with just using alpha testing instead of blending. Alpha test just discards pixels with alpha less than a threshold. It’s less expensive than blending and you don’t need to sort objects to use it. You only need blending when you want to use semi-opaque objects (alpha between 0 and 1).