Decals and flipbooks

A Part emitter can carry pictures on its particles. Each Decal or Texture on the particle’s template is a layer, with its own transparency, colour and brightness over the particle’s life. A flipbook is a numbered series of pictures that a layer shows one after another. Exercise 5 puts a flipbook on a particle step by step.

What it makes possible:

• A flame that plays once as it rises. One layer, a flipbook from the Inventory, Flipbook ▸ Mode OneShot.
• A mesh with a base picture that fades and a second picture that flickers. Two layers, each with its own Transparency graph.
• Two flipbooks at different speeds on one particle. Two layers, each with its own Mode Loop and its own Framerate.
• Cards that never match. StartRandom on: each particle starts on a frame of its own.

Where the rows are

Section of the Properties panel	Holds
Decals	The list of layers, and the rows of each layer.
Flipbook	How frames are played: Mode, Framerate, StartRandom and Reverse.

Both sections are on Part emitters only. Both start collapsed.

Beam, Trail emitter and ImageLabel emitters have a Flipbook section of their own. It is described on their pages.

The Decals list

What a layer is

Every Decal or Texture that sits directly inside the RenderTemplate is one layer. The Decals section lists them.

Layers are told apart by name. Two layers with the same name are told apart by their order.

The Appearance rows act on the part. They do not reach a layer. The Transparency graph in Appearance fades the part, and the Transparency graph of a layer fades one picture. See Decal layers.

+ Add Decal

The + Add Decal button adds a Decal to the template of every selected emitter.

• The Decal is placed on the Front face.
• It is named Decal. If that name is taken it is named Decal2, then Decal3, and so on.
• It is hidden in the template. It shows on the particles through its own Transparency row.

The header of a layer

Control	Action	Result
The header	Click	The entry folds, or unfolds.
Active	Click	The layer is marked as one that the Inventory’s Insert fills. The pill starts off.
×	Press	That Decal is removed from every selected emitter.

The rows of a layer

Row	Kind	Starts at	Unit	What it does
Transparency	Graph	0	0 to 1	How far the picture is seen through, over the particle’s life.
Color	Colour	The Decal’s own colour		The tint of the picture. Drawn as a gradient, it changes over the particle’s life.
Brightness	Graph	1		Multiplies the Color, over the particle’s life.
Flipbook	List	Auto		Which flipbook the layer plays.
Mode	List	Inherit		Inherit, OneShot, Loop, PingPong or None.
Framerate	Two numbers	Empty	Frames per second	The layer’s own speed for Loop and PingPong.
Start Random	Switch	The setting of the Flipbook section		Starts each particle on a random frame of this layer.
Reverse	Switch	The setting of the Flipbook section		Plays this layer’s frames backwards.

The last four rows take their values from the Flipbook section until they are set on the layer.

• Mode on Inherit uses the Mode of the Flipbook section.
• Framerate left empty uses the Framerate of the Flipbook section. The empty box reads min, max (inherit).
• Start Random and Reverse use the switches of the Flipbook section until they are set here.

The colour put on the picture is the layer’s Color multiplied by the layer’s Brightness.

Two numbers typed into Transparency or Brightness give each particle one value between them. The value is picked for each layer separately.

The Flipbook row of a layer

Choice	What the layer plays
Auto	The first layer plays the frames that sit directly in MeshFlipbooks. Every other layer plays nothing.
None	Nothing.
The name of a folder	The frames in the folder of that name inside MeshFlipbooks.

The list offers one choice for each folder inside MeshFlipbooks.

A layer with nothing to play shows the picture its Decal has in the template.

The Active pill

The Active pill marks the layers that a flipbook from the Inventory is put on. With no layer marked, Insert adds a new layer. Filling the folder from the Inventory gives every case.

The pill is not used when a single picture is inserted.

Several emitters selected

• The list shows the layers of the first emitter.
• An edit reaches the Decal of the same name on every selected emitter.
• When the names differ, a banner reads Mixed decals - edits reach items that have the same layer.

The Flipbook section

Row	Kind	Starts at	Unit	What it does
Mode	List	OneShot		None, OneShot, Loop or PingPong.
Framerate	Two numbers	30	Frames per second	The speed of Loop and PingPong. Each particle picks a value between the two. Hidden while Mode is OneShot.
StartRandom	Switch	Off		Each particle starts on a random frame.
Reverse	Switch	Off		Plays the frames backwards.

These rows do two things.

First, every layer uses them until the layer sets its own.

Second, they play a flipbook on two things that are not layers:

On the template	What the flipbook changes
A SurfaceAppearance	Its ColorMap. In Studio only. See Limits.
A MeshPart with no Decal, no Texture and no SurfaceAppearance	The MeshPart’s own texture.

Both play the frames that sit directly in MeshFlipbooks. If there are none, both play the first folder inside it, in alphabetical order.

How the frames are played

These rules hold for the Flipbook section, for each layer, and for Mesh Frames.

Mode	What plays	Worked figure
None	Nothing.
OneShot	The frames once, spread across the particle’s life. Framerate is not used. The last frame shows at the end of the life.	8 frames over a Lifetime of 2 seconds: each frame shows for 0.25 seconds.
Loop	The frames at the Framerate, starting again from the first after the last.	8 frames at 16 frames per second: 2 loops a second.
PingPong	The frames forwards, then backwards, at the Framerate. The end frames are not shown twice.	8 frames make a round trip of 14 steps. At 14 frames per second that is one round trip a second.

A PingPong round trip of n frames takes 2n − 2 steps.

• Framerate takes two numbers. Each particle picks one value between them when it is made. One number gives every particle the same speed.
• Two numbers typed with the larger first are put in order.
• A Framerate below 0.1 is treated as 0.1.
• StartRandom starts each particle on a random frame.
• Reverse plays the frames from last to first.
• Playback follows the particle’s own clock. Timescale slows it, stops it and runs it backwards.

With StartRandom on, OneShot wraps around. It runs to the last frame, carries on from the first, and ends one frame before the frame it started on. With 8 frames and a start on frame 6, the particle shows 6, 7, 8, 1, 2, 3, 4, 5.

The MeshFlipbooks folder

Transform puts an empty MeshFlipbooks folder under every Part emitter. See MeshFlipbooks.

The folder takes two layouts. Both may be used in one folder.

MeshFlipbooks
  1
  2
  3
  Flame
    1
    2
    3

Layout	Holds	Played by
Flat	Frames named 1, 2, 3, directly in the folder	The first layer, with its Flipbook row on Auto. A SurfaceAppearance. A MeshPart’s own texture.
Named folders	One folder for each flipbook, each holding frames named 1, 2, 3	The layer whose Flipbook row names that folder.

• A frame is a Decal or a Texture. Only its picture is used.
• Frames are played in the order of their numbers. 01 and 02 are read as numbers and sort correctly.
• A name that is not a number counts as 0. Such frames come first, in no fixed order. Keep frame names numeric.
• A gap in the numbers does no harm. Only the order counts.
• Frames may be added, removed and put in a new order by hand.
• Selecting a frame inside MeshFlipbooks shows the emitter in the Properties panel.
• A folder edited by hand can be saved to the Local Inventory. See The Inventory.

Filling the folder from the Inventory

Select the Part emitter, then press Insert on a flipbook in the Inventory. The + on a thumbnail does the same.

Insert makes the frames as Decals named 1, 2, 3 and so on. Where they go depends on the emitter.

The emitter has	Insert does	The frames go to
One or more layers marked Active	Each Active layer gets the frames in a folder of its own and is set to play it. Frames the layer had before are replaced.	MeshFlipbooks/<layer name>
No Active layer and no SurfaceAppearance	A new layer is added to the template, on the Front face, named after the Inventory entry. Its Transparency starts at 0.	MeshFlipbooks/<entry name>
A SurfaceAppearance and no Active layer	The frames go directly into the folder. Flat frames are replaced. Named folders are kept.	MeshFlipbooks

• If the name of a new layer is taken, a number is added: Name2, then Name3.
• Three flipbooks inserted one after another give three layers. Each plays its own flipbook.
• Insert does not change Mode or Framerate.
• With several emitters selected, each gets its own frames.
• The Decals list refreshes at once.
• Each Insert is one step in Studio’s undo history.
• The emitter counts as selected when its RenderTemplate, or anything inside its MeshFlipbooks, is selected.

NOTE

Insert reads Inserted! even when nothing suitable is selected. A Folder named after the entry then appears in the Workspace, holding the frames. It is storage only. Delete it, select the emitter and press Insert again.

A single picture

Insert on a single picture, not a flipbook, writes to one place on a Part emitter:

The template has	The picture goes to
A SurfaceAppearance	Its ColorMap.
No SurfaceAppearance, and a Decal	The first Decal.
No SurfaceAppearance, no Decal, and a Texture	The first Texture.
None of these	Nowhere. Nothing is written.

To put a picture on one chosen layer, select that Decal inside the RenderTemplate in the Explorer. Then press Insert.

Other emitter types

Selected	Insert on a flipbook
A Beam emitter	Empties the BeamFlipbooks folder and fills it.
A Trail emitter	Empties the TrailFlipbooks folder and fills it.
An ImageLabel emitter	Empties the ImageFlipbooks folder and fills it. Flipbook Source is set to Decals.

A frame in these three folders must be a Decal.

Limits

CAUTION

In Animate mode no flipbook plays on a Part emitter. The Transparency, Color and Brightness rows of each layer do play, on the template’s own Decals. The Decals get their own values back afterwards.

CAUTION

A flipbook on a SurfaceAppearance plays in Studio only. In a running game the change is refused, and one warning is printed. For a flipbook that must play in the game, use a Decal or Texture layer.

• The Decals list is on Part emitters only.
• On a Part with a SpecialMesh whose mesh frames carry pictures, Mesh Frames sets the picture of the first layer. That layer’s own flipbook is skipped. See Mesh Frames.