Program MrSnugglekins

Main program


Max gives the program a detailed introduction in a long comment at the start of the program code. We paraphrase a paragraph of it here and add hyper-links for your convenience. We look forward to reading the tutorial and we recommend a viewing of Max's video of his impressive skeletal animator.

To see the latest source code for the program (and my other projects), go to my Github page at The version used in this game is an older version. (The new version is loaded from a DLL and goes about things differently. I will be writing documentation and tutorials soon!) This older version cannot really be used to make 3D games without the required animation program. The animation program this version uses is really horrible. I have since rewritten it, but the output files are different and are not compatible with this version of the library. To see the new version of the animation program in action (with the new version of the library) go to

Keep track of the Max's progress at

Code of the main program

///                                                                         ///
///                  MR SNUGGLEKINS AND THE GIANT SACK OF CATNIP            ///
///                         by Max Foster                                   ///
///                               ///
///                                                                         ///

   Copyright (c) 2011 Max Foster

A game created for the mini competition.
The aim of the competition was to create a game with eight buttons or less, with 50 bonus points for each
unused button. 
There were eleven entries, and they were scored on the following criteria: Graphics & Audio;
Ease of Control; Stability & lack of bugs; Innovation & Creativity; Fun Factor. This game came fourth
place, while using all eight buttons, and came first place without button bonuses!
For full results, see here:

Most of the assets for the game, including the 3D models, music and shaders were created by myself. The
only assets that were not created by me were the fonts (which I have purchased rights to) and sound effects
(although I did make the shopkeeper voiceovers).

Uses OpenGL and SDL with the SuperMaximo GameLibrary, also created by myself. To see the latest
source code for it (and my other projects), go to my Github page at
The version used in this game is an older version. (The new version is loaded from a DLL and goes about
things differently. I will be writing documentation and tutorials soon!). This version cannot really be
used to make 3D games without the required animation program. The animation program this version uses
is really horrible. I have since rewritten it, but the output files are different and are not compatible
with this version of the library. To see the new version in action (which also uses the new version of
the library) go to

(Also, the reason I use Objects instead of Classes is that I like the syntax a bit better, and they allow
me to call constructors/destructors of superclasses like a regular method without actually creating a
new instance).

The OpenGL code used in this game and in the SuperMaximo GameLibrary does not use the fixed function
graphics pipeline, but instead uses the programmable shader pipeline. The fixed function pipeline has
been deprecated in modern OpenGL. (Actually, it has been removed completely, but a compatability profile
exists in OpenGL implementations to support the old functionality). The reason I mention this is because
many tutorials online, such as the popular tutorials, teach the fixed function pipeline,
and therefore the OpenGL code used in this game might look alien to some people who maybe followed these
To learn about the programmable pipeline (which I HIGHLY recommend!), I recommend the OpenGL SuperBible 5
book (although you have to read most of it because it teaches you the author's own library at first rather
than OpenGL and then eases you into the OpenGL.
You don't actually learn how to draw anything completely by yourself until the last few chapters).


/////          GAME README     //////////

NOTE: This readme was provided with the competition entry. When the game is compiled with the
NO_BUTTON_LIMIT compiler directives, use WASD to move around, and use the mouse to aim, using
the left mouse button to fire. Navigate the menus by point and click with the mouse.
If the NO_BUTTON_LIMIT compiler directive is not used, then the controls outlined in this readme are valid.

You play as Mr Snugglekins, who has stashed a great big sack of catnip for himself to enjoy!
Unfortunately, the government of Cattyland has put a tax on catnip, but you refuse to pay, so they send in
the police; an army of spambots!

Defend your sack of catnip from the spambots for as long as possible in this 3rd person shooter adventure!

W : move forward / move up through menus
S : move backward / move down through menus
A : strafe left
D : strafe right
J : rotate anticlockwise
L : rotate clockwise
I (AKA 'fire' or 'trigger' in game) : shoot / do action / make menu selection
Esc : go to pause menu (if in game)

In the top left hand corner is the health for your sack of catnip.
The the top right hand corner is your score.
In the bottom left hand corner is your health. If you die, you will be delayed in your defence by five seconds!
In the bottom right hand corner is your ammo, money, and 'euphoria meter' (shaped like a lightning bolt).
You build up your euphoria meter as you destroy enemies. When it reaches maximum capacity,
you get hypercharged and your running speed, firing speed and bullet damage are doubled for a period of time.
In front of your cat there is a line which is either white or red, which is to help you aim.
When the line is red then you are guaranteed to hit an object.

When you destroy enemies, you'll get some money for it. Spend your hard earned cash in the shop!
To go to the shop, go to the pause menu by pressing Esc and navigate to the 'SHOP'.
Use the W and S keys to look through the different items you can buy, and press fire (I) to buy an item.

There are four guns to choose from, which can be bought from the shop or picked up as a random drop from a spambot:

Kitty Gun : Your standard gun
Akat : A hitscan gun; it hits the target instantly. Your sight line will change red when you're in range of an
       object and can do damage to it.
Bird Catcher : A shotgun
Anti Mech : A bazooka which reloads slowly, but does large amounts of damage and objects in the surrounding
            explosion area when it hits are hurt with splash damage (including yourself!)

Pickups are dropped randomly by enemies.
Healthpack : A white box with a red cross. Replenishes some health.
Euphoria Pack : An orange box with a black lightning bolt. Fills up some of your euphoria meter.

Turrets can be bought from the shop. When a turret is bought from the shop it is placed in the closest
free space to you in the direction you are facing. If you are standing in front of an obstacle, the
turret will be built in front of the obstacle. They automatically scan for and shoot at enemies.
The Kitty Gun turret is an automatic Kitty Gun and the Akat turret is an automatic Akat.

Turrets can be upgraded by walking near them, and by pressing fire (I). You will then be shown a turret
upgrade menu. You can navigate through the options with WASD and press trigger to select an option to buy.
Firepower upgrades increase the firing speed, range upgrades increase the firing range, and health upgrades
help you in case you go on a firing spree and accidentally start hurting your own turrets!
Turrets can be 'hacked'. If an enemy starts hacking your turret, it will become immobile and start to
turn purple. When it has been fully hacked by the enemy, it will try to attack you! Either destroy the
turret or run up to it and press fire (I) to hack it back onto your side. If you destroy a hacked turret
you will get some money and points for it, but if you destroy a turret on your team then you'll lose points.

You get money and points for destroying enemies.
Drones : These are the bog-standard spambots. They're pretty weak and pretty dumb, but there's lots of them!
Hackers : Hackers are basically fast drones, except that they can hack turrets!
Mech : These are great, hulking, axe wielding spambots. They have a large amount of health and can do a lot
       of damage to your sack of catnip.

You can forfeit the game from the pause menu. This will destroy your sack of catnip.

When your sack of catnip reaches zero health, you lose! Your score breakdown will be shown and you'll
be asked to enter your name.
Use W and S to pick letters, and A and D to go backward and forward spaces. Press trigger (I) to confirm.


program MrSnugglekins;
{$mode objfpc}{$H+}     { $define COMPILE_LEVEL_EDITOR}

  SysUtils, Math, Display, ShaderClass, MusicClass, FontClass,
  GraphicalAssetClasses, InitialisationAndFreeing, ButtonClass, CatClass,
  SpambotClass, GlobalGameVariables, turretclass, Audio, bulletclass, dglOpenGL,
  explosionclass, floatscoreclass, gameactorclass, gunclass, hudclass, Input,
  pickupclass, sackclass, sceneryclass, shopkeeperclass, sightclass,
  SMSDL, SoundClass, spawnpointclass, TextureClass
  {$ifdef COMPILE_LEVEL_EDITOR} , LevelEditor {$endif} ;

procedure mainMenu;
  logo : PSprite;
  tempCat : PCat;
  tempDrone : array[0 .. 2] of PDrone;
  time, extraHeight : real;
  i : integer;
  //load up the buttons, logo, cat, drones and music for the main menu
  resetMainMenu := false;

  logo := new(PSprite, create('logo', 'assets/sprites/logo.png', 0, 0, 500, 150));

  tempCat := new(PCat, create(0, 0));
  tempCat^.setPosition(20, 0, 0);
  tempCat^.rotate(0, -15, 0);

  for i := 0 to 2 do
      tempDrone[i] := new(PDrone, create(0, 0, true));
      tempDrone[i]^.setPosition(-30 + (30 * i), -28, 0);
      tempDrone[i]^.rotate(-15, 0, 0);
      tempDrone[i]^.scale(0.6, 0.6, 0.6);

  time := 0;
  xDistance := 0;
  yDistance := 30;
  zDistance := 0;
  rotation := 0;
  respawning := false;
  showHighScores := false;
  highScoreDisplayDelay := 0;

    //draw a dark blue background by telling the font shader to set its colour tint
    //to dark blue, and then drawing a white rectangle, scaling to the size of the screen
    fontShader^.setUniform4(EXTRA0_LOCATION, 0.0, 0.0, 0.2, 1.0);
    whiteScreen^.draw(0, 0, -1000, 0, skyXScale, skyYScale);

    //set up matrices and shaders for 3D drawing
    tintShader^.setUniform4(EXTRA1_LOCATION, 1.0, 1.0, 1.0, 1.0);

    //Increment the frame of the cat and drones so they dance to the exact tempo of the music
    tempCat^.setFrame(1 / 1.125, true);
    for i := 0 to 2 do
      tempDrone[i]^.setFrame(1 / 1.125, true);

    //Make the cat and drones jump realistically by moving their y positions
    //according to a sine wave, except for when they hit the floor
    extraHeight := sin(degToRad((time / 40) * 360));
    if (extraHeight < 0) then
        extraHeight := 0;
        time := 0;
    tempCat^.draw(false, true);

    for i := 0 to 2 do
        tempDrone[i]^.setY(-28 + (extraHeight * 2));
        tempDrone[i]^.draw(false, true);

    //Draw the outline for the cat and drones
    tempCat^.draw(false, true);
    for i := 0 to 2 do
      tempDrone[i]^.draw(false, true);

    //Draw logo and highscores or menu buttons
    logo^.draw(10, 10, -1);
    if (showHighScores) then
        for i := 0 to 9 do
            fontShader^.setUniform4(EXTRA0_LOCATION, 1.0, 1.0, 1.0, 1.0);
            tenneryBold^.write(highScores[i].name, 30, 160 + (20 * i), -1, true, 0, 0.4, 0.4);
            tenneryBold^.write('-', 160, 160+(20 * i), -1, true, 0, 0.4, 0.4);
            tenneryBold^.write(intToStr(highScores[i].score), 200, 160 +(20 * i), -1, true, 0, 0.4, 0.4);
        tenneryBold^.write('Press any button to return to the main menu', 30, 380, -1, true, 0, 0.5, 0.5);

        if (trigger and (highScoreDisplayDelay > 20)) then
            showHighScores := false;
            highScoreDisplayDelay := 0;
          highScoreDisplayDelay += compensation;

    //If the player has just returned from the main menu from gameplay, reset the
    //necessary settings
    if (resetMainMenu) then
      time := 0;
      tempCat^.setPosition(20, 0, 0);
      tempCat^.rotate(0, -30, 0);
      xDistance := 0;
      yDistance := 30;
      zDistance := 0;
      rotation := 0;
      respawning := false;
      resetMainMenu := false;

    //Refresh the screen and increment the timer
    time += compensation / 1.125;
  until quit;

  //Dispose of the cat, drones, logos and buttons loaded at the beginning of the
  dispose(tempCat, destroy);
  for i := 0 to 2 do
    dispose(tempDrone[i], destroy);
  dispose(logo, destroy);


  {Initialise everything, and then either go to the game (or level editor if
  COMPILE_LEVEL_EDITOR is defined. The highscores are read in before going to
  the main menu, which acts as the outermost game loop. Afterwards, free all the
  assets so the RAM and GPU memory is nice and clean!}





Can you modify the code in any way and predict the effects of your changes? Have you been able to create your own map using it. Could you use it to help you develop your own program using OpenGL?

Programming - a skill for life!

by Max Foster: L6 Age ~17