From Anonymous Tipster comes one of the more sophisticated homebrew PSP games: ThrottleX 0.3. It supports online play and it comes with a level editor.

Improvements over the previous version are:

• Round wheels

• Level Editor (the download below contains the PDF tutorial)

• Save/View Replays

• 15 new levels

• Downloadable levels

• Online Infrastructure play

• De-activated auto-reset (use Tri if you've failed)

• Analog steering

• Sound effects

• Better camera

Basic Game Controls:

• DPad/Analog to steer
• Cross to accelerate
• Circle to brake
• Square to reverse
• Triangle to reset

Anonymous Tipster included information about the online play feature of the game:

• If you wish to host, or are having connection problems, you need to forward port 55555 TCP and 55556 UDP on your router.

• Online play is currently only for 2 players due to lag, but once the engine is improved, I hope to add up to 16 players.

• The server gets to set "upload" speed. The lower the value, the more times information is sent. Lower the value if the game seems to jump along. Raise the value for greater stability.

• This online play is experimental so may not be 100% stable (not sure anything is 100% stable) but I hope you'll enjoy the addition.

There's also support for downloadable levels. If you've made a level (using the level editor; there's more about the level editor below), you can share it with others.

There's also a replay feature. To save a replay:

1. Press Square at the mission complete screen

2. Press Square whilst at the pause screen

3. Press Square in multiplayer when you have completed the level, and it zooms out.

To play a replay, you simply go to "view replay" on the main menu and move left and right to select the replay. If the one you want is not there, press square to recache the directory.

Here's more of what Anonymous Tipster had to say about the editor:

• There is a simple tutorial attached which should ease you into using the editor.

• I'd recommend not rotating the blocks in more than one axis, as I think my GU->ODE matrix conversion is slightly flawed and may produce odd results.

• Down the bottom left is an image depicting which 'mode' you are in, a camera dictates camera movement, straight arrows dictate translation, curved arrows dictate rotation, two straight arrows dictate scaling and three objects dictate object selection.

• Camera:

• Up/Down is zoom in/out

• Left/Right is rotate left/right about current object

• Tri/Cross is up/down

• Movement:

• Up/Down/Left/Right is X/Z translation

• Tri/Cross is Y translation

• Rotation:

• Controls different depending on where you view from, similar to Movement.

• Scaling:

• Same as Movement.

• Selection:

• Left/Right scrolls through objects

• When on movement, you can tap select to duplicate the current object. Note that you do not need to tap select again to "set" it in place, or you will end up with two objects in the same place.

• Start brings up the menu, where you can change between blocks, spawn, goal/gate and power ups. Clicking Add Object will add a new object near the origin, Delete Object will remove the currently selected object. Test Level runs that level, and can be exited via start then triangle.

• Level Options:

• Level Name: The title that comes up whenever the level is reset

• Creator: Who you are

• Game Type: Click X to toggle goal or gate mode

• Save Level as .trx: saves level to SavedLevels folder

• Filename: the filename to save

• Load Level: Lists levels in SavedLevels to load

• Clear Level: Deletes all data on current level

• Power Ups:

• Gravity: Changes gravitational pull. Default is -64 in the Y field

• Boost: Gives the car an impulse in that direction

• Jet Pac: Gives the player some fuel for the jet pac

• Jet Pac Controls:

• This will require some skill to get used to. When you have some fuel, hold L/RTrigger to boost you up in the air. Left/Right turns you in the air and Up/Down controls the nose of the car, a lower nose means you travel forward faster (same principle as a helicopter). Note that these controls are only available when powering the jet pac.