trouble with vaporTrails

[digdug]

How to make vapor trails looks better ?
why the vapor trails of this weapon looks messed up ?
It's a missile launcher with vapor trails that lanches 6 missiles at the same time

Can somebody tells me (if possible) how to make the trails looks better when the missile are not lock onto a target ? Currently 3 of them are shot straight and 3 are diagonal, and I don't know why.
Maybe it's just a limitation of the vaportrail effect.

Here is the weapon...

Code: Select all

		<!-- Napoleon Launcher -->

	<ItemType UNID="&itNapoleonLauncher;"
			name=				"Napoleon Launcher"
			level=				"6"
			value=				"19000"
			mass=				"4500"
			frequency=			"rare"
			modifiers=			"MajorItem; Launcher; Ammo; Specialty"

			description=		"The Napoleon is a 6 muzzled missile launcher, each ammo cartridge contains 6 mini missiles that automatically track on the nearest target."
			>

		<Image imageID="&rsItems1;" imageX="0" imageY="480" imageWidth="96" imageHeight="96"/>

		<Weapon
				fireRate=			"30"
				powerUse=			"10"
				 
				launcher=			"true"
				>

			<Missiles>
				<Missile ammoID="&itNapoleonMissile;"
						type=			"missile"
						lifetime=		"120"
						damage=			"blast:1d6+2; WMD4"
						missileSpeed=	"50"
						maneuverability="2"
						directional=	"true"
						hitEffect=		"&efFragmentationExplosion;"
						sound=			"&snMissileLauncher;"
						vaporTrailLength="40"
						vaporTrailWidth="110"
						vaporTrailWidthInc="5"
						vaporTrailColor="0xff, 0x00, 0x00"
						>

					<Image imageID="&rsMissiles2;" imageX="0" imageY="0" imageWidth="32" imageHeight="32" imageFrameCount="0" imageTicksPerFrame="0"/>

					<Fragment
							count=			"5d6"
							type=			"missile"
							lifetime=		"5"
							damage=			"blast:1d6+2; WMD4"
							missileSpeed=	"5-48"
							>
							
						<Effect>
							<ImageAndTail 
									imageID=			"&rsMissiles4;" 
									imageX=				"0" 
									imageY=				"0" 
									imageWidth=			"16" 
									imageHeight=		"16"
									imageFrameCount=	"4"
									imageTicksPerFrame=	"1"
									
									length=				"32"
									width=				"8"
									primaryColor=		"0xff, 0xff, 0xff"
									secondaryColor=		"0xc0, 0xc2, 0x85"
									/>
						</Effect>
					</Fragment>

				</Missile>


			</Missiles>

			<Configuration aimTolerance="5">
		<Shot posAngle="-90" posRadius="10" angle="-3"/>
		<Shot posAngle="90" posRadius="10" angle="3"/>
		<Shot posAngle="-90" posRadius="5" angle="-2"/>
		<Shot posAngle="90" posRadius="5" angle="2"/>
		<Shot posAngle="0" posRadius="0" angle="-1"/>
		<Shot posAngle="0" posRadius="0" angle="1"/>
		
		
		
	</Configuration>
			
		</Weapon>

	</ItemType>
		
		
	<!-- Napoleon missile -->

	<ItemType UNID="&itNapoleonMissile;"
			name=				"Napoleon missile"
			level=				"6"
			value=				"40"
			mass=				"40"
			frequency=			"uncommon"
			numberAppearing=	"8d20"
			modifiers=			"Consumable; Missile"

			description=		"The Napoleon is a non military multi missile compatible with the Napoleon Launcher. Each cartridge contains in 6 mini missiles."

			sortName=			"Napoleon.20"
			>

		<Image imageID="&rsItems1;" imageX="0" imageY="96" imageWidth="96" imageHeight="96"/>
	</ItemType>

[Cygnus.X1]

I think it's a limitation of the GFX rendering engine. I've noticed in my experiments that the vapor trails are limited to 16 directions (or something like that), so if you are 1 'tick' from a cardinal direction, the vapor trial comes out in a cardinal direction even if the missile was fired at, say, 95 degrees (just past cardinal East).

hard to explain

[digdug]

so, I have to use only certain angles to get a nice pattern.

I will experiment with that a little

[digdug]

OK, so I tested some configuration and I cannot manage to get the vaporTrails do what I want.

Example, I'm using the weapon posted before with this configuration:

Code: Select all

<Shot posAngle="0" posRadius="0" angle="-27"/>
		<Shot posAngle="0" posRadius="0" angle="27"/>
		<Shot posAngle="0" posRadius="0" angle="-18"/>
		<Shot posAngle="0" posRadius="0" angle="18"/>
		<Shot posAngle="0" posRadius="0" angle="-9"/>
		<Shot posAngle="0" posRadius="0" angle="9"/>

Ships is static however the trails are moving to the left.

Some of them are misaligned, just as the trails source is the top left corner of the playership image.








And here I made an overlay of all the images where is clear that the trails are going left.

http://img6.imageshack.us/img6/5048/overlayds0.png

[digdug]

More problems/glitches

even with 1 single trail:

if the ship is facing at angle 0 (up) the trail is rendered with a considerable delay.
if the ship is facing at angle 180 the trail is NOT rendered.
if the ship is facing 90 or 270 it seems that the trail is rendered 2 times for each missile.

[Cygnus.X1]

bug report: graphics rendering engine -> missile vapor trails -> specific ship radians causes counter-intuitive behavior

That's some tricky screen-shot-ery, I'm impressed!

But it doesn't help except to prove that you aren't crazy, the expected behavior really is off.

I've notice the missing vapor trails at degree 0 before too when tweaking the Phaser weapons, somewhat fixed by increase effect's 'width' attribute, but still incredibly noticable.

[george moromisato]

Nice debugging.

I think there are two things going on:

1. Vapor trails are aligned to one of the 20 rotations.
2. The code for painting polygons has some edge conditions that cause them to paint improperly when they are small.

I've fixed both for the next version.

[And BTW, sorry, but I don't have a firm date for the next version yet. But I'm definitely working on it.]

[Cygnus.X1]

falls over stunned

Hi George! Nice ta meetchya! [/i]

[digdug]

Thank you very much, George.

[Aury]

Oh, I think it should be mentioned that the same problem appears when a "bolt" type weapon (of at most intensity 3) is drawn. When facing (0 and 180 or 90 and 270, I forget which, probably the first), the bolt is not drawn, and it increases in width and visibility until you get to an alignment perpendicular with the first.

I'd think this is caused by the same problem George stated above.