Having Problems With Sequences

[OcelotWalrus]

Okay, so I've made a custom unit, and it works fine. But when I use a custom-made sprite image, it crashes with the error Index was outside the bounds of the array.. This happens because of the Facings: 8 line. Here're the data:

sequence:

jet1:
	idle:
		Filename: bits/jet1.png
		Facings: 8
	muzzle:
		Filename: muzzle2.png
		Length: 3
		Facings: 8
		Tick: 50
	icon:
		Filename: jet1-icon.png

sprite:

yaml for the sprite:

FrameSize: 28,22
FrameAmount: 8
Offset: 0,0
Author: Cromha
License: GPL-3+

I found after doing some research, that by using a default sprite, it works perfectly, but if I happen to just edit one single pixel, and save the image, it crashes with the same error. For some reasons the game can't load the sprite. It happened to me with many animated sprite. I'm pretty sure the error happen because of the format of my image maybe? I really can't find out how to fix this issue, after investigating a lot. I'd like to have you guys' help!

P.S. I've made the sprite using Krita.

Full Log

Exception of type `System.IndexOutOfRangeException`: Index was outside the bounds of the array.
   at OpenRA.Graphics.SpriteCache.LoadReservations(ModData modData) in /home/lolo/Documents/vscode-cloned-repositories/OpenHV/engine/OpenRA.Game/Graphics/SpriteCache.cs:line 74
   at OpenRA.Graphics.SequenceSet.LoadSprites() in /home/lolo/Documents/vscode-cloned-repositories/OpenHV/engine/OpenRA.Game/Graphics/SequenceSet.cs:line 108
   at OpenRA.ModData.PrepareMap(String uid) in /home/lolo/Documents/vscode-cloned-repositories/OpenHV/engine/OpenRA.Game/ModData.cs:line 148
   at OpenRA.World..ctor(String mapUID, ModData modData, OrderManager orderManager, WorldType type) in /home/lolo/Documents/vscode-cloned-repositories/OpenHV/engine/OpenRA.Game/World.cs:line 197
   at OpenRA.Game.StartGame(String mapUID, WorldType type) in /home/lolo/Documents/vscode-cloned-repositories/OpenHV/engine/OpenRA.Game/Game.cs:line 193
   at OpenRA.Game.LoadShellMap() in /home/lolo/Documents/vscode-cloned-repositories/OpenHV/engine/OpenRA.Game/Game.cs:line 528
   at OpenRA.Mods.Common.LoadScreens.BlankLoadScreen.StartGame(Arguments args) in /home/lolo/Documents/vscode-cloned-repositories/OpenHV/engine/OpenRA.Mods.Common/LoadScreens/BlankLoadScreen.cs:line 99
   at OpenRA.Game.InitializeMod(String mod, Arguments args) in /home/lolo/Documents/vscode-cloned-repositories/OpenHV/engine/OpenRA.Game/Game.cs:line 514
   at OpenRA.Game.Initialize(Arguments args) in /home/lolo/Documents/vscode-cloned-repositories/OpenHV/engine/OpenRA.Game/Game.cs:line 425
   at OpenRA.Game.InitializeAndRun(String[] args) in /home/lolo/Documents/vscode-cloned-repositories/OpenHV/engine/OpenRA.Game/Game.cs:line 309
   at OpenRA.Launcher.Program.Main(String[] args) in /home/lolo/Documents/vscode-cloned-repositories/OpenHV/engine/OpenRA.Launcher/Program.cs:line 32

[OcelotWalrus]

I found out about some sort of "palette indexed .png" format, but it doesn't really help. I'd just like to know how to make sprites for the game. There's really nothing on the wiki about sprite creation, and the OpenRA wiki doesn't tell much.

[GraionDilach]

Sounds like you forgot to merge the metadata into the sprite with OpenRA.Utility --png-sheet-import.

Yes, we keep the metadata separately as well in the repo, but that's only for readability, the game reads the PNG metadata from the sheet itself. (It's a tEXT block within the PNG, so it's compliant with the format.)

[OcelotWalrus]

Thanks man! I just have got a minor issue now: the sprite doesn't get the player color applied. And the green background gets displayed.

[GraionDilach]

Yeah, that sounds to be caused by your unfamiliarity with traditional '90s sprite handling methodics.

OpenRA can use both 32 bit PNGs and 8 bit "indexed" PNGs, with OpenHV only using the latter (I actually don't even know how 32 bit remap works, examples are only within the TibDawnHD mod). Using 8 bit PNGs, you're limited to a maximum of 256 colors and traditionally games applied remap via either overriding a gradient of slots with the remap (C&C, Warcraft) or just copying one section of the palette to another for remap (TTD).

Just export out the OpenHV palette from another unit spritesheet and reuse that palette.

[OcelotWalrus]

By exporting out another unit spritesheet's palette, you mean using the same colors? So I also need to export my PNGs to 8-bit colors right?

[OcelotWalrus]

I actually made the sprite by copying the same colors as other OpenHV sprites. And I checked, it's indeed 8bit pngs. Maybe it's the alpha channel that causes the issue?