gifs for day 4

src/uxn_tutorial_day_4.gmo

@@ -450,6 +450,8 @@ however, this repetition might not allow for a smooth movement like what we can
 
 the following program allows us to control the horizontal position of our square using the arrow keys.
 
+=> ./img/screencap_uxn-moving-square.gif animated gif showing a square moving horizontally in the screen, apparently controlled by a human.
+
 note the similarities between the previous program, and what we covered on day 3!
 
 ```
@@ -551,8 +553,8 @@ EQU2 ( is x equal to screen width - 8 ? )
 ,&continue JCN
 
  &increment
-  ( increment sprite/pos-x )
-  .sprite/pos-x LDZ2 #0001 ADD2 .sprite/pos-x STZ2 
+      ( increment sprite/pos-x )
+      .sprite/pos-x LDZ2 #0001 ADD2 .sprite/pos-x STZ2 
 
  &continue
 ```
@@ -768,6 +770,8 @@ note that it uses a sequence similar to the previous programs:
 
 the clear sprite section is not actually needed in this case because of the colors that are used, but it would be when using colors with transparency in them :)
 
+=> ./img/screencap_uxn-animation.gif animation of a diagonal stripe inside a pixelated square. the diagonal moves from bottom right to top left
+
 ```
 ( hello-animation.tal )
 
@@ -873,8 +877,12 @@ we can use these macros to divide the frequency in our code:
       .Screen/addr DEO2 ( set computed address )
 ```
 
+
+=> ./img/screencap_uxn-animation-quarterspeed.gif animation of a diagonal stripe inside a pixelated square. the diagonal moves from bottom right to top left. it moves slower than the previous one.
+
 ah, way better!
 
+
 ## not powers of two
 
 note that if you want to divide the frequency to numbers that are not powers of 2, you might start to see some glitches approximately every 4 seconds: this is due to framecount overflowing and not giving a nice sequence of results for those divisors.