How to create a pixel editor?

Question

C++ / C#

Basically, I'm building a simple editor, and I'm stuck on rendering pixels. SFML.
I made my own canvas and rendered a matrix on it by VertexArray but ran into performance issues. Looks like I went in the wrong direction.

Answer 1

Well, I figured it out myself. In my opinion, work through sf::Image remained a better option. And processing Viewport. I got the coordinates via mapPixelsToCoords.

Answer 2

Maybe you should use DirectX/Vulkan/OpenGL , but it depends on where the performance hits and where the problems occur.