suzanne.soy/racket
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

world plus scene

Browse Source 
svn: r6133
This commit is contained in:
Matthias Felleisen 2007-05-04 02:04:16 +00:00
parent 7ca2762e7e
commit c8f158f5d5
1 changed files with 13 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
collects/teachpack/htdp/Docs/world.thtml
View File

@ -4,7 +4,7 @@
<p>The teachpack provides two kinds of functions. The first five allow
students to simulate a small world of animated drawings and games:
<menu>
<li><code>{(idx run-simulation)} : Nat Nat Number [Nat -> Image] -> true</code><br>
<li><code>{(idx run-simulation)} : Nat Nat Number [Nat -> Scene] -> true</code><br>
<code>(run-simulation width height r create-image)</code>
creates and shows a <code>width</code> x <code>height</code> canvas,
starts a clock, ticking every <code>r</code> (usually fractional) seconds,
@ -28,11 +28,17 @@ students to simulate a small world of animated drawings and games:
</pre>
</p>
<p>
The <code>Stop</code> button on the frame allows users to stop the clock
and thus the simulation. It also enables the <code>Images</code> button,
which then allows users to create images of all the steps taken since the
beginning of time.
<p>The teachpack assumes two basic kinds of data:
<ul>
<li><code>World</code>, which is something you must define;
</li>
<li><code>Image</code>, which are either inserted into DrScheme via the
"Special" menu or constructed from the functions below; and
</li>
<li><code>Scene</code>, which are created from <code>Image</code>s. Indeed,
they are just special images.
</li>
</ul>
</p>
<li><code>{(idx big-bang)} : Nat Nat Number World -> true</code><br>
@ -114,7 +120,7 @@ students to simulate a small world of animated drawings and games:
<code>(empty-scene width height)</code>
creates a width x height "scene" (frame with origin in NW)
<li><code>{(idx place-image)} : Image Number Number Scence -> Scene</code><br>
<li><code>{(idx place-image)} : Image Number Number Scene -> Scene</code><br>
<code>(place-image image x y scene)</code>
places image at (x,y) into scene; (x,y) are comp. graph. coordinates