DSI Projects

GFKAEV^‡ Details

I recently had a chance to iron out some more details regarding GFKAEV^‡ (two 6-hour plane trips will do that). Here's the gist of the game. You must launch your spacecraft from your home planet and safely reach your destination, negotiating the dangerous space in between.

You choose the power and angle from which to launch. Then while in flight you take full control of your ship. You rotate it using the D-pad and thrust with a button. Firing lasers, decoys, and transport beams is accomplished by other buttons.

Your ship will be pulled and pushed by various gravitational effects due to planets, stars, and nebulas. Enemy turrets will also shoot at you. Overheating poses another problem as remaining too close to a star will cause damage (the act of firing or being hit will also produce heat). Be careful not to melt!

Sometimes your mission will be purely to reach your target. Other times you will need to rescue stranded space craft before arriving at your destination.

Your ship will be outfitted with several pieces of equipment. You'll have shields and a laser to get past the gun turrets. You can also use decoys to fool the turrets. You'll use a transport beam to rescue your fellow spacemen.

How well you finish each level will determine how many upgrade points you earn. There might also be upgrades floating around in the level for you to grab. Some upgrades include:

Better energy storage (energy is used for fuel as well as powering shields, laser, and transport beam)
Improved shielding (consumes less energy per hit)
More powerful lasers (along with a faster recharge time)
Better heat dissipation systems
More I have yet to think of

Status

Items in bold are more recent.

Here's the list of what I've done so far:

Player and turret shields added (with crappy hand-drawn art)

If a player/turret gets hit and still has enough shield energy left to absorb the damage then only the shield is displayed.
If the shield is low on power (or has no power) then an explosion is shown and damage is done to the target.

Collision detection for laser beams added
Turrets rotate to face the player and fire when facing it

Implemented a table for the various types of turrets. That way I can have one turret which rotates quickly, but fires slowly; or another which rotates slowly but has a powerful laser; etc.
Note that any laser can hit any target once fired. So if you fly between two turrets correctly, they could both fire at you, miss, and end up hitting each other.

Created new object for enemy turrets
Player can now fire laser
Added HUD to show vectors for movement, thrust, and gravity
Player can rotate and thrust
Collision detection for the player hitting planets added
Objects exert appropriate gravity on the player
Menu at beginning of level lets you select angle and power
Screen scrolls when actual playfield is larger than screen size
Objects display on screen

Issues

I'm having trouble displaying a background successfully in hi-res mode (which is what I'm using in the game). It works fine in low-res, but when I change it to 640x480 the background flickers (like it's only being drawn every other frame). I hope I can eventually find a solution as the game screen will be very bland without any backgrounds.
My code ran into the limit for computation during one frame. I optimized one of my routines and the problem went away, but I'm waiting for it to creep up again before I'm done. I have identified several more optimizations should this become a consistent problem. If necessary I'll code the major routines in assembly (I really hope it doesn't come to that).

Check out the screenshots below to get an early look at the game (these were produced using the Screen Grabber - see Spotlight for more details). Click on each one to get a description of the screen.

GFKAEV^‡ Screen Shots

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