Stoke Field Force SpaceWarp

Available in Stoke MX 2.0 and higher. Last Edited on May 1, 2014.

Introduction

The Field Force SpaceWarp creates a Force Field from any Stoke Vector field.

It lets you pass Stoke Field data into any sub-system of 3ds Max that supports force SpaceWarps, including MassFX, Particle Flow, Legacy Particles, Hair&Fur, FumeFX etc.

Note that other than typical Force SpaceWarps in 3ds Max, the transformations of the Field Force object have no effect on the force application - the world space location of the selected Field Source is the only relevant factor.

Also note that most Vector fields (e.g. the Velocity field) in Stoke describe the actual speed in units per second, while the Force SpaceWarp is interpreted as an Acceleration value by 3ds Max. Thus, the value represents the derivative (change in speed) and not the speed itself, and might require an additional multiplier to produce visible results. The multiplication could be performed either inside the source (if it is Magma-based), or using the Force Scale parameter in the Field Force UI.

User Interface

../../_images/STK2_PRTField_UI_Light.png

Parameters Rollout

Field Source pickbutton

  • Use this pickbutton to pick the Stoke Field object to create a Force field from.
  • Hit the H button to select by name.

[>] button

  • Clicking the button next to the Field Source pickbutton will open a context menu with the following options:
    • Select Field Source - selects in the scene the object that was picked as the field source. Grayed out if no source was picked.
    • Hide Field Source - togge the hidden state of the picked field source. Grayed out if no source was picked. A checkmark will be displayed if the source is hidden.
    • Remove Field Source - clears the Field Source pick, disconnecting the SpaceWarp from the Field Source.

Vector Channel Name drop-down list

  • This list will display all Vector fields defined in the selected Field source.
  • The values of the specified field will be used as acceleration values for any supported 3ds Max system including legacy particle systems, Particle Flow, MassFX etc.

Force Scale value spinner

  • Default is 1.0.
  • Lets you scale the magnitude of the source Vector Channel to adjust the Force strength without editing the original source field.

Icon Size value spinner

  • Default is 50.0
  • Controls the viewport size of the object’s icon.

Object Creation Workflow

The Stoke Field Force Space Warp object can be created using several methods:

Using the Stoke Menu

The Stoke menu is installed automatically with the product and provides shortcuts to all major components.

  • Click the Stoke menu in the 3ds Max Main Menu bar.
  • Select the “Create Field FORCE SpaceWarp Object - hold SHIFT to create at World Origin” entry.
  • If you are holding SHIFT while selecting the menu option and no other objects are selected in the scene, a Stoke Field Force will be created at the World Origin 0,0,0.
  • If you are holding SHIFT while selecting the menu option and one or more objects are selected in the viewport, the selection will be searched for valid Field objects. The first selected Field object will be automatically assigned to the Field Force as source.
  • If you are NOT holding SHIFT while selecting the menu option, you will enter the standard creation mode of the Stoke Field Force object:
  • Click in the viewport on the current grid to define the one position of the object.
  • At this point, the creation procedure will exit and the 3ds Max Command Panel will be switched from Create to Modify mode to let you start working on the object’s settings.

Using A MacroScript On A Toolbar or Keyboard Shortcut

  • Alternatively, you can customize the 3ds Max UI to place the same MacroScript used by the Stoke menu on a toolbar, QuadMenu or assign to a dedicated Keyboard Shortcut.
  • Simply use the Main Menu > Customize > Customize User Interface dialog to locate the “Stoke” category and assign the MacroScript as needed.
  • The actual creation procedure will be identical to the one described in the Stoke Menu section above.

Using the 3ds Max Create Tab in the Command Panel

You can also use the regular 3ds Max workflow for object creation which is similar, but slightly different from the Stoke Menu / MacroScript approach.

  • Activate the Create tab of the 3ds Max Command Panel
  • Make sure you are in “Space Warp” mode.
  • Select “Stoke” from the Category drop-down list
  • Click the “Field Force” button to enter creation mode
  • Click in the viewport to define the position of the Field Force object.
  • Note that 3ds Max will remain in Field Force object creation mode and you can start creating another object immediately, or Right-Click to exit creation mode.

Using MAXScript

You can create a Stoke Field Force object by executing the following code:

Field_Force()

The resulting object will be created at the origin.