add example images

README.md

@@ -1,3 +1,12 @@
 # android-shaders
-GLSL shaders made in/for the [Shader Editor app](https://f-droid.org/en/packages/de.markusfisch.android.shadereditor/) on fdroid.
+GLSL shaders made in/for the [Shader Editor app](https://f-droid.org/en/packages/de.markusfisch.android.shadereditor/) on F-Droid ([source](https://github.com/markusfisch/ShaderEditor)).
 
+### binary_clock.glsl
+Displays hours, minutes and seconds in binary as rows of filled circles.
+
+![](demo/binary_clock.png)
+
+### interactive_game_of_life
+A rainbow-coloured simulation of [Conway's Game of Life](https://conwaylife.com/wiki/Conway%27s_Game_of_Life). The edges of the screen are randomised so that the pattern never stabilises. Pressing on the screen will turn on cells in a small radius.
+
+![](demo/game_of_life.png)