# Space Coordinate Systems

(Difference between revisions)
 Revision as of 18:14, 2 November 2012 (view source)HE-SCOTT (Talk | contribs) (→Multiple objects)← Older edit Latest revision as of 20:11, 5 November 2012 (view source)HE-ZACH (Talk | contribs) Line 54: Line 54: * Create an object, such as a fence or signpost.  If working in Clean Engine and not sure which object to use, check [[Create a signpost]] for how to create a sample object. * Create an object, such as a fence or signpost.  If working in Clean Engine and not sure which object to use, check [[Create a signpost]] for how to create a sample object. * Navigate your view so that you have a good overall view of the object. * Navigate your view so that you have a good overall view of the object. − * Using the Rotate tool, [[Image:Rotate.gif]] "tip" the object to an odd angle + * Using the Rotate tool, {{rotate}} "tip" the object to an odd angle * Click on the "Select & Translate" tool {{translate}} * Click on the "Select & Translate" tool {{translate}} ** Note the translation [[gizmo]] within the object is oriented up and down in "world space" ** Note the translation [[gizmo]] within the object is oriented up and down in "world space" Line 69: Line 69: * Select all objects at once, with Ctrl+click or dragging the mouse to select them all * Select all objects at once, with Ctrl+click or dragging the mouse to select them all * Go into World Space mode [[Image:Coordinate.png]] * Go into World Space mode [[Image:Coordinate.png]] − * Select the Rotation tool [[Image:Rotate.gif]] + * Select the Rotation tool {{rotate}} * Rotate all of the objects and note how they're all moving as a group * Rotate all of the objects and note how they're all moving as a group * Go into Local Space mode [[Image:LocalSpace.png]] * Go into Local Space mode [[Image:LocalSpace.png]]

## Contents

This is an easy-level tutorial that goes over the differences between Local Space and World Space coordinate systems.
Menu to toggle back and forth, from the Transform Toolbar

Space coordinate system are one of the following:

• Local space - position relative to a node's object space
• World space - position relative to the world space

## Overview

Sometimes it is helpful to move or rotate an object in relation to its own "local" space, rather than world space. For example, if a fence object is placed and then duplicated, it may be helpful to move the next object along the axis of the first fence, to allow them to line up properly.

Rotation can also be important as to whether it's occurring on a world space or local level.

To toggle back and forth from World Space to Local Space, use the "World and Local Space tool" on the Transform Toolbar, either by selecting the appropriate option in the dropdown menu, or just clicking on the button to toggle back and forth.

Tip: With the Select & Translate tool, holding down the Ctrl key and then hovering the mouse over the gizmo, will show the current axes of movement. See the Tutorial section below for more information on how this works.

### Multiple objects

Special cases exist for when multiple objects are selected.

Select & Translate:

• When multiple objects are selected and an attempt is made to move them in Local Space mode, the objects will be moved based on the local space of the first object that was selected.

Rotate:

• In World Space mode, rotation will be around the centroid of all of the objects
• In Local Space mode, rotation will cause each selected object to rotate around its own local space

### Gizmos

If a gizmo (set of axes) is visible, it will often change orientation depending on which mode (local or world) is active.

The image on the left, shows the gizmo of the object oriented in world space (straight up and down). The image on the right, shows the gizmo when local space is activated (the gizmo aligns with the object).

Note: Some tools from the Transform Toolbar, such as Scale, and Bounds, will always work in Local Space, regardless of whether World or Local space is selected.

## Tutorial

Object oriented in World Space (note the snap grid lines aligned with the world, not the object)
• Start off in "World Space" mode, by choosing "World space" in the Transform toolbar. The icon should like this, with the blue arrow pointing straight up.
• Create an object, such as a fence or signpost. If working in Clean Engine and not sure which object to use, check Create a signpost for how to create a sample object.
• Navigate your view so that you have a good overall view of the object.
• Using the Rotate tool, "tip" the object to an odd angle
• Click on the "Select & Translate" tool
• Note the translation gizmo within the object is oriented up and down in "world space"
• Hold down the Ctrl key to activate the Snap grid, and hover the mouse over the gizmo axes, to see how they are oriented in world space
• Move the object, and note how it moves up and down in world space
• Toggle the Space coordinate button in the Transform Toolbar to Local Space mode. This can be done by choosing that option in the dropdown menu, or simply clicking on it to toggle it back and forth.
• Notice how the Translation gizmo is now oriented in relation to the object
• Hold down the Ctrl key and hover the mouse over the gizmo axes, and note how they are now oriented in local space
• Move the object with the translation tool, and notice how it moves along the axis of the object itself.
Object oriented in Local Space (note the snap grid lines aligned with the object, not the world)
• Duplicate the object with Ctrl+D
• Select the duplicated object and move it, and note how since it moves along the axis of the original object, it is easy to align the duplicate object with the original one.
• Duplicate multiple copies of the object, and place them so each can be seen individually
• Select all objects at once, with Ctrl+click or dragging the mouse to select them all
• Go into World Space mode
• Select the Rotation tool
• Rotate all of the objects and note how they're all moving as a group
• Go into Local Space mode
• Rotate all of the objects at once, trying each of the three axes (red, yellow, and green), and note how the objects move, each rotating relative to their own local space.