Hello everyone

I have search all over Google trying to find how can i make a day and night effect in 2D and i could not find anything.

so how can i make my game looks like its night time and day time?
I'm using c++ and sfml.

thank you

For 2D games this is normally done by telling your artist to draw things that way.

If you want some type of dynamic light it gets quite a bit harder, you could probably just darken everything (either by reducing the color intensity in your images or by drawing a dark, semi opaque image over everything) but the results won't be great.

SFML Sprites have a SetColor function. The default value is sf::Color(255, 255, 255, 255) but if you set it to 128,128,128,255 then it's drawn darker. For night though, you'd want something of blueish hue not pitch black.

I know that the creator of this software is using dynamic lighting but i really don't care about that. i just want to be able to make things dark a bit.

If it doesn't have to be dynamic then you could just draw it as you want it, make a separate image where the completely dark parts are black and the light parts transparent and draw it over your level.

If you want things dynamic then you have to create this image at runtime (Exactly how this is best done depends on the game in question, the usual 3D methods such as volumetric shadows and shadowmapping could be adapted for 2D but may not perform well enough if done in software).

The image you linked is actually rendered using XNA (Which really is a 3D API):

You could read this:
http://www.gamedev.net/page/resources/_/technical/graphics-programming-and-theory/dynamic-2d-soft-shadows-r2032 which describes how to do it using OpenGL, and you should be able to adapt that to SFML