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The Edit Surface Properties Tool

The Edit Surface Properties tool gives you control over the properties of the surfaces of Bezier patches and brush faces. You can use it to apply and change materials and modify their scale, shift and rotation on the surface. Additionally, sophisticated options are available to determine the looks of a surface.

The Edit Surface Properties tool can be activated by clicking on the related icon in the Tools toolbar or by pressing the SHIFT+V shortcut key.

Left-Clicks: Selecting and Picking

A normal click with the left mouse button on a surface (Bezier patch or brush face) in the 3D view accomplishes two tasks:

  • it selects the surface (you can see how it becomes highlighted by a reddish overlay), and
  • it picks the properties of the surface and updates the values in the related dialog accordingly (the Orientation and Material sections are updated).

As usual, you can hold the CTRL key to select more than one surface at a time. Please note that CTRL-clicked surfaces are selected, but not picked. That is, only the first selected surface (left mouse button click without CTRL) implies the pick operation.

In fact, selection and picking are actions that are independent of each other:

  • Both: A normal left mouse button click performs both.
  • Selection only: Holding the CTRL key while clicking toggles the selection, but doesn't pick.
  • Picking only: You can also pick but not select by holding the ALT key during the mouse click, which activates the eyedropper mode. The properties of such clicked surfaces will appear in the dialog, but their selection status won't change.

Finally, you can also hold the SHIFT key during a left mouse button click. The SHIFT key does not add anything special when the click is on a Bezier patch, but for brush faces, it causes all faces of the affected brush to become selected. (If CTRL is not held at the same time, one of the brush faces will also be picked for updating the dialog values.) You can combine the SHIFT with the CTRL key in order to toggle the selection status of all faces of the brush.

Brushes that were selected when the Edit Surfaces Tool was activated are automatically changed into face selections.

Material and Orientation

Once you have selected one or more desired surfaces, you can modify their material and orientation attributes.

This is easily achieved by the appropriate controls of the related dialog. While pressing one of the small + or - buttons and choosing another material takes immediate effect, please note that entering a new numerical value into the Scale, Shift or Rotation fields by hand requires an additional press on the RETURN key to become effective.

If you have multiple surfaces selected at the same time, the new value of the changed attribute is applied to all of them, while all other attributes are left alone. This allows you for example to replace the material on a number of surfaces all at the same time, and for example adapt their scale, while the shift, rotation and other surface aspects are left unchanged. This is especially worthwhile when the selected surfaces possibly have different values for the same attribute.

Right-clicks: Quick and Special Application

TODO

The Surface Properties dialog

Orientation

Adjusts how the material is mapped onto a surface.

  • Scale: Scales the material in direction of the x or y axis.
  • Shift: Adds an offset in direction of the x or y axis before the material is mapped onto the surface.
  • Rotation: Rotates of the material in degree.

Material

  • Group: Selects the materials group.
  • Current: Selects the currently applied material. Can be selected by using the Browse button.
  • Globally Replace: Opens the Material Replace dialog (see here).

Alignment

  • Fit: Stretches and shifts the material until it fits exactly onto the surface.
  • T: Shifts the material until it concurs with the top edge of the surface preserving its scale (this option is not available for bezier patches).
  • L: Shifts the material until it concurs with the left edge of the surface preserving its scale (this option is not available for bezier patches).
  • R: Shifts the material until it concurs with the right edge of the surface preserving its scale (this option is not available for bezier patches).
  • B: Shifts the material until it concurs with the bottom edge of the surface preserving its scale (this option is not available for bezier patches).
  • C: Shifts the material until it is centered in the surface preserving its scale (this option is not available for bezier patches).
  • wrt. World axes: The texture plane from which the texture is mapped onto the surface is parallel to worlds axes (for more details see last section). This works also as a switch, so you can force the texture plane to be parallel to the world axes by selecting this checkbox.
  • wrt. Face plane: The texture plane from which the texture is mapped onto the surface is parallel to the face axes (for more details see last section). This works also as a switch, so you can force the texture plane to be parallel to the face plane by selecting this checkbox.
  • Treat multiple as one: Determines whether multiple selected surfaces are treated as one face, when aligning a material on them. If you would fit a material on multiple faces while this flag is active, the material would be matched to the biggest extends from all surfaces and then mapped onto the single surfaces.

Tool mode

  • Hide Selection Overlay: Disables the red selection overlay that is normally shown, when selecting a surface.
  • Right MB mode: Determines how a material is applied onto a surface if you rightclick on the target surface.
    • Apply Normal: Applies both the material and the orientation properties shown in the dialog.
    • Apply Material only: Applies only the material ignoring other properties shown in the dialog.
    • Apply View Aligned: Applies a material by doing a parallel projection from the active camera viewport onto the target surface.
    • Apply Edge Aligned: Applies a material by aligning the material edges of the face from which the material was lifted and the target face (this option is not available for bezier patches).
    • Apply Projective: Projects a material using the texture plane axes from the last picked up surface. If no texture plane axes are available (e.g. if you performed your last pick on a bezier patch whose material wasn't applied trough a plane projection) this apply mode doesn't work.
  • to all Sel.: Performs the Right MB mode action to all selected surfaces.

Using the Edit Surface Properties tool

On activation of the edit surface properties tool, its dialog is opened immediately. When activating the tool for the first time, you'll find default orientation values and the default material displayed in the dialog.

To edit the properties of a surface you have to select one by left clicking on it. This results in a pickup of its current surface properties into the dialog, so you will probably see a change in the orientation values.

Now you can adjust these values using the +/- Buttons or by entering a value and pressing ENTER. This will immediately apply the changed value onto the currently selected surface(s). You can also use the alignment buttons to automatically shift and scale a material so it is properly aligned onto the surface. Note that this does not change the shift and scale values in the dialog. To see the newly created orientation values in the dialog, you would have to reselect the surface.

Another possibility to pick up material properties is to use the eye dropper. This is done by left clicking onto a surface while holding down the ALT key. Using the eye dropper, surface properties are picked up and shown in the dialog but the clicked surface is not selected.

As hinted above changes in the dialog are applied to all selected surfaces. To select more than one surface you have to hold down CTRL and left click on a surface. This will add the surface to the current selection. Note that when selecting a surface holding down CTRL its properties are not picked up as it is done with a normal left click.

Applying orientation values trough the dialog only applies the value that is changed, so if you edit the x shift value, only this value is applied to all currently selected surface. You can also apply an orientation value to the current selection without changing it by selecting its input field and just pressing ENTER.

Another way to apply orientation values from the dialog is by right clicking onto surfaces. Doing this the right mouse button mode is used to apply the properties shown in the dialog onto a surface. These modes are described above. You can also use the apply mode on all currently selected surfaces by clicking the to all Sel. button.

Sometimes it is desirable to adjust orientation values in the dialog without applying them immediately to a surface. To do this you have to deselect all surfaces by pressing CTRL+Q. Now you can edit the orientation values in the dialog freely. If you want to apply the orientation values to a selection of surfaces, you have to select them holding down CTRL even when selecting the first surface, so your orientation values are not overwritten. Then you can click the to all Sel. button and apply the prepared orientation values using the current right MB mode.

It might happen that picking up surface properties (either by selecting or with the eye dropper tool) doesn't work and the message “Picking orientation values from objects with custom UVs is not possible.” appears on the screen. This means that the material is applied in a custom way and the dialog is not able to read definite orientation values from this surface. It is still possible to select such surfaces and apply new values to them, thus ending their custom state.

Another special case are bezier patches that are newly created or whose material is applied using the FIT button. In both cases the material is not plane projected onto the patch, but applied in a way only suitable for bezier patches. Picking up the properties of such a bezier patch results in blue colored orientation values. This shows that applying these values onto a face might have an unexpected result since these values have another meaning for fit applied bezier patches.

The Edit Suface Properties Tool mouse usage

  • Right click
    • no key pressed: Applies surface properties shown in the dialog using the selected apply mode only to the clicked surface.
    • SHIFT key down: Applies surface properties shown in the dialog using the selected apply mode to all faces of a brush, if performed on a brush (no effect on bezier patches).
  • Left click
    • no key pressed: Selects a surface, clearing the previous selection and picking the surfaces properties up.
    • SHIFT key down: Selects all surfaces of a brush clicked on (no effect on bezier patches), but picks up only the properties of the clicked surface.
    • CTRL key down: Adds a surface to the current selection without picking up its properties.
    • ALT key down: Doesn't affect the selection and only picks up the clicked surfaces properties.

The Edit Suface Properties Tool keyboard shortcuts

  • SHIFT+A
    • Activates the Edit Surface Properties tool.
  • CTRL + Q
    • Deselects currently selected surfaces.

Advanced considerations on Texture Mapping

This graphic shows how textures are mapped onto faces. Note that the graphic shows a top down view, so the texture planes y axis is not visible in it.

Textures are mapped on a face by parallel projecting the texture from a texture plane P onto a face. The texture plane from which the texture is projected can be any plane in worlds coordinate system, but is usually chosen to be parallel to the face on which the texture should be projected (see faces of brushes A and D in the graphic).

In the texture plane, a point of origin is needed to determine where the first texture is drawn onto the plane. This point of origin is the normal vector from the plane to the world origin and therefore unique for every plane. Starting from this point the texture is tiled onto the plane whereat the length of the x axis vector is the textures width and the y axis vector (not visible in this graphic) is the textures height. The texture repeats itself along the x and y axis (see red dashes).

The vectors that decide the width and height of the texture can be increased or decreased in size to scale the texture. This is what happens when you increase or decrease the Scale value in the Edit Face Properties dialog (see above). The Shift values in the dialog are added as an offset the point of origin of the texture plane to shift the texture in x or y direction. The Rotation value is used to rotate the point of origin and in this way rotate the texture.

How a texture is projected onto a face depends on the position of the face in relation to the texture plane. In this example the face of brush A lies exactly in the dimensions of the x axis vector and therefore the texture fits exactly on the faces width. The face of brush D however lies outside the regular tiling of the texture plane and therefore the texture is mapped shifted onto the face starting at the first half of the textures x coordinates.

As said above the texture plane can be any plane in the worlds coordinate system. This results in texture planes that are not parallel to the face the texture is projected on. In this case the texture is projected in the same way as before, but the result is a contorted texture on the face due to the fact that a smaller texture area is mapped onto a bigger face area (see brushes B and C in graphic).

In the Edit Face Properties dialog the wrt. World axes and wrt. Face plane show if the texture plane of this face is parallel to the world axes or to the face plane. It is also possible to set these values and therefore explicitly set the texture plane to world axes or face plane.

mapping/cawe/editingtools/editfaceprops.1197052865.txt.gz · Last modified: 2013-01-07 12:07 (external edit)