The '''ValueCopy''' component is used to ensure that a value from one [[Type:IField|field]] is the same as another field via a one-way relation or a two-way relation with writeback. The source and target types must be [[value types]].
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== Fields ==
== Fields ==
{{Table ComponentFields
{{Table ComponentFields
|Source|IField`1|TypeString0=IField<float>| The source to copy the value from.
|Source|{{RootFieldType|RelayRef`1|[[Type:IField`1|IField`1]]<T>}}|TypeAdv0=true| The source to copy the value from.
|Target|IField`1|TypeString1=IField<float>| The target to copy the value to.
|Target|{{RootFieldType|FieldDrive`1|T}}|TypeAdv1=true| The target to copy the value to.
|WriteBack|Bool| Allow Target to write back to Source.
|WriteBack|Bool| Allow Target to write back to Source. See [[Drives#Write Backs|write backs]].
}}
}}
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== Usage ==
== Usage ==
Drives the target's value with the source's value. When using WriteBack, changes made to the Target are local while editing it. When the user is done setting it, it writes via a network sync to change the Source value. If the Source and Target are the same, the value will be completely local, and no network sync happens when changing the value. When using the ValueCopy to make fields local like this, joining users will have the host's value by default.
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This component ensures that the value in the <code>Target</code> field is equal to the value in the <code>Source</code> field. To do this, it [[drives]] the <code>Target</code> field to give it exclusive access to the value, then whenever the value in the <code>Source</code> field updates, it will write the new value to the <code>Target</code> field.
When <code>WriteBack</code> is enabled, the target field will have the ability to be changed. Changes made to the target field will then be written back to the source field.
Using a ValueCopy from a field to itself will essentially make the field read-only. If WriteBack is enabled, it presents an interesting combination of the locality of drives and writing of values: It will make the value of the field local to each individual user. This may be used as a version of [[Component:ValueUserOverride|ValueUserOverride]] that doesn't do any kind of network writes, but it should be noted that users joining the session will first receive the value from the host user before it gets changed. As such, it should only be used when the value doesn't quite matter specifically or gets updated frequently.
A ValueField<int>'s Value is being driven to be 7 from another ValueField<int>'s Value. The one in pink is the one being driven.
File:ValueCopyExample2.png | 512px | A ValueField<[[Type:int|int]]>'s Value is being driven to be 7 from another ValueField<int>'s Value. The one in pink is the one being driven.
File:ValueCopyExample3.png | 512px | A ValueCopy with <code>WriteBack</code> enabled. The target field is being edited to 4, which changes the source field as well.
File:ValueCopyExample1.png | 512px | A ValueField<[[Type:bool|int]]>'s Value is being self driven with a WriteBack. Changes to this value will be local.
The ValueCopy component is used to ensure that a value from one field is the same as another field via a one-way relation or a two-way relation with writeback. The source and target types must be value types.
Allow Target to write back to Source. See write backs.
Usage
This component ensures that the value in the Target field is equal to the value in the Source field. To do this, it drives the Target field to give it exclusive access to the value, then whenever the value in the Source field updates, it will write the new value to the Target field.
When WriteBack is enabled, the target field will have the ability to be changed. Changes made to the target field will then be written back to the source field.
Using a ValueCopy from a field to itself will essentially make the field read-only. If WriteBack is enabled, it presents an interesting combination of the locality of drives and writing of values: It will make the value of the field local to each individual user. This may be used as a version of ValueUserOverride that doesn't do any kind of network writes, but it should be noted that users joining the session will first receive the value from the host user before it gets changed. As such, it should only be used when the value doesn't quite matter specifically or gets updated frequently.
Examples
A ValueField<int>'s Value is being driven to be 7 from another ValueField<int>'s Value. The one in pink is the one being driven.
A ValueCopy with WriteBack enabled. The target field is being edited to 4, which changes the source field as well.
A ValueField<int>'s Value is being self driven with a WriteBack. Changes to this value will be local.
A ValueField<int>'s Value is being driven to be 7 from another ValueField<int>'s Value. The one in pink is the one being driven.
A ValueCopy with
A ValueField<int>'s Value is being self driven with a WriteBack. Changes to this value will be local.
