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by David Dunham

In my last How To article for the Ambrosia Times I discussed how to make an EV ship plug in resource into an EVO plug in resource. Now I'll show you how to outfit that ship, and create a new weapon for it. Once again, I owe most of this to DYNA Systems' EVO Object Formulas, and Matt Burch's EVO Bible, also available at the above address. For actually making your plug in I suggest using either ResEdit, the free resource editor available from Apple, or EV Edit, Ben Chess' EV/O plug editor.

To create a new outfit resource, the resource ID number must be between 182 and 255 for Escape Velocity, for EV Override, the ID number must be greater than 202 and less than 255. So if your EV "outf" resource falls in this range it will be OK, if not add to the ID number until it is within range.

202 < ID# EVO outf =( ID# EV outf + X )< 255
where X is the number you needed to add to the EV ID number to make it within EVO range.

The position of your new outfit is determined by subtracting 128 from the ID number of your new EVO outfit.

New Outfit position = (ID# EV outf + X) - 128
Next you need to create two PICT resources. The first is a normal picture of the item and the second is a thumbnail of the item. This pict is shown when the outfit ship window comes up and is 32 x 32 pixels, the first is shown when the player selects the item and is 100 x 100 pixels.

The resource ID number of the first, larger PICT resource is calculated by adding 6000 to the New Outfit position.

ID# selected PICT outf = [(ID# EV outf + X) - 128] +6000
The resource ID number for the second and smaller PICT resource is calculated by adding 6101 to the New Outfit position.

ID# thumbnail PICT outf = [(ID# EV outf + X) - 128] +6101
Next, you need to create 3 STR resources. The first is a short name for the New Outfit and must be less than 15 characters, the second is the same in lowercase, the third is also lowercase but must be less than 20 characters and is plural.

The ID number of the short outfit name is calculated be adding 3000 to the new outfit position.

ID short outf name = [(ID# EV outf + X) - 128] =3000
The ID number of the lower case name is calculated by adding 3200 to the new outfit position.

ID lowercase outf name = [(ID# EV outf + X) - 128] + 3200
The ID number of the plural outfit name is calculated by adding 3400 to the new outfit position.

ID plural outf name = [(ID# EV outf + X) - 128] + 3400
Finally you need to create a description - "desc" resource. This is the text displayed when a player selects the item in the outfit ship window.

The ID of the new outfit description is calculated by adding 3000 to the new outfit position.

ID # outfit desc = [(ID# EV outf + X) - 128] = 3000
That should make your EV outf resource EVO compatible. Now, how to make a weapon for that outf resource.

To create a new weapon - "weap" resource you need to set the ID number equal to or higher than 153 and less than, or equal to 190 for Escape Velocity. For EV they need to be higher than 163.

1632 < ID# New EVO weap = ID # EV weap + X < 190
where X is the number you add to the EV weapon resource to make it higher than 163.

The position of your new weapon resource is calculated by subtracting 128 from the its ID number.

pos weap = [ID # EV weap + X] - 128
If the new weapon is a projectile weapon, then you need to create 2 PICT resources, a 36 sprite grid whose width and height are a multiple of 8, and the corresponding mask. The ID number of the projectile sprites must be greater than or equal to 232 and less than or equal to 398, and an even number.

232 < ID #projectile sprites < 398
The Id number of the mask is calculated by adding one to the ID number of the projectile sprites.

ID # projectile mask = ID # projectile sprites + 1
A spin resource must also be created. The spin resource must be greater than or equal to 214 and less than or equal to 262.
214 < ID # weap spin < 262
For a sound to be played when this weapon is used you must create a sound - "snd" resource formatted to 8 bits and at 11.127 kHz with no compression. The ID number of the sound resource must be greater than or equal to 218 and less than or equal to 223. But, the ID number of the sound cannot be 223.
218 < ID # weap sound < 263 but not = 223
This covers the basics of converting an EV "outf" resource and "weap" resource to an EVO "outf" and "weap" resource. This does not cover what attributes your weapon resource may have, its speed, power, whether it is a guided weapon or not. For a more complete explanation of these attributes and the fields that determine them I suggest you study the EV/O Bible.

Thanks again to DYNA systems and EVO Object Formulas.


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