Modeling Tutorials > Using Photos to Model Façades >
Correcting the Texture

To correct the texture on selected faces, you add additional mapping information for those faces. There are a number of ways to do this, but the Unwrap UVW modifier is the most versatile and interactive way: This lesson shows how to use Unwrap UVW.

Adding texture detail is a matter of how much time you want to spend, and how you plan to use the model. If the model will appear only in a long shot, you might be able to dispense with texture correction. If the model will appear in a medium shot or a close-up, you might have to go through these steps.

For the purposes of this lesson, we use the final rendering as a guide:

This is a medium shot. Facade1, on the left, is in shadow: But at another time of day, you would be able to see the right sides of the doorways. So we will show how to correct the sides of the doorway, and the doorstep.

The windows are too far away to see detail; the roof is seen only from below; and the sides of the house are obscured by other houses. So we won’t go through the steps for correcting these details, but at the end of this lesson, we show how the details might be corrected. (The completed model, facade_modeling_completed.max, has many texture corrections that these lessons don’t describe.)

Set up the lesson:

1. Continue working on your scene from the previous lesson, or open \modeling\facades\facade_modeling_03.max.
2. If you open the file, select the façade, go to the Modify panel, and make sure that (Show End Result) is on for all three levels of the stack.

Add an Unwrap UVW modifier:

1. Select Facade1.
2. Go to the Modify panel. In the modifier stack, click the UVW Mapping entry to make this modifier active.
3. From the Modifier List, choose Unwrap UVW.
4. In the modifier stack, click (the plus-sign icon) by the Unwrap UVW entry to expand the Unwrap UVW sub-levels, then click the Face sub-object level to make it active.

Correct the texture on the left-hand doorjamb:

1. Orbit (or use the ViewCube), zoom, and pan the viewport so you have a good view of the right side of the doorways.

   The sides appear streaked, because they are at right angles to the texture projection of the UVW Map modifier.

2. Click and Ctrl+click to select both doorjamb faces.
   NoteYou can adjust some settings for both doorjambs at once, because they are parallel to each other.
3. On the Modify panel Projection rollout, click to turn on (Planar Map), then click (Align To X).

   Now the doorjambs are correctly aligned with the fac1.jpg texture. However, they show the entire façade, which is not quite what we want.

4. Click (Planar Map) again to turn it off.
   ImportantIf you forget to turn off Planar Map, later you won’t be able to use controls in the Edit UVWs dialog.
5. Click to select only the left-hand doorjamb.
6. On the Modify panel Edit UVs rollout, click Open UV Editor.

   3ds Max Design opens the Edit UVWs dialog.

7. On the Edit UVWs dialog toolbar, choose “Map #11 (fac1.jpg)” from the background pattern drop-down list. (The map number might vary.)

   Now the main window of the dialog displays fac1.jpg.

8. On the second of the lower toolbars, the Transform/Display toolbar, click to turn on (Display Only Selected Faces).

   Now the geometry shown in the Edit UVWs dialog (the red mesh) represents only the left-hand doorjamb face.

9. On the Edit UVWs dialog toolbar, click to turn on (Freeform Mode).

   The face mesh now shows handles at its edges and corners. With Freeform Mode, you can scale the face by dragging a corner handle, rotate the face by dragging a side handle, and move the face by dragging from the interior of the face.

10. Drag a corner to scale the face so it is roughly the size of a doorjamb in the bitmap.
    TipMove the Edit UVWs dialog so you can also see the left doorjamb in the viewport. That way, you can see your texture-mapping changes interactively, as you make changes in the dialog.
11. In the Edit UVWs dialog, drag the face to the right, so it covers the right side of the central pillar.
12. On the Edit UVWs dialog toolbar, click (Mirror Selected Subobjects).

    In the viewport, you can see how the correction looks.

This is the pattern for using Unwrap UVW to correct textures on faces with poor texture projection: Essentially, you “fake” the texture by choosing some part of the original texture that looks well when applied to the surface that needs correcting.

Correct the texture for the right-hand doorjamb:

1. With the Edit UVWs dialog still open, click to select the right-hand doorjamb.
   TipSometimes toggling (Display Only Selected Faces) can help refresh the Edit UVWs window.
2. On the Edit UVWs dialog toolbar, turn on (Freeform Mode), then drag the upper-right corner of the doorjamb face to scale it so it is roughly the size of a doorjamb in the bitmap.
3. Drag the face a bit to the right, so you can see the edge of the shrub.
4. On the Edit UVWs dialog toolbar, click (Mirror Selected Subobjects).

   Once again, you can see the correction in the viewport.

5. Close the Edit UVWs dialog.
6. Deselecting the faces makes it easier to see the corrections you made.

Correct the texture on the doorsteps:

The doorsteps are a little tricky, because the photo has no information about that portion of the building. To compensate, we use the lintel texture: Although the lintel is wood, when scaled up in size it can pass for stone.

1. Click and Ctrl+click to select the doorstep faces (there are four faces on the left, and three on the right).
2. On the Modify panel Projection rollout, click to turn on (Planar Map), then click (Align To Z).

   Now the doorsteps are correctly aligned with the fac1.jpg texture.

3. Click (Planar Map) again to turn it off.
4. On the Modify panel Parameters rollout, click Edit to open the Edit UVWs dialog.
5. In the Edit UVWs dialog, scale and move the doorstep faces so they are on top of the lintel beam in the bitmap.
6. Close the Edit UVWs dialog.

A close-up rendering of the doorways shows your texture corrections better than the viewport can.

Save your work:

- Save the scene as facade1_textured.max.

Extra Credit: Mapping the Windowsills, Window Jambs, and Sides of the House

As we mentioned at the beginning of this lesson, it isn’t necessary to correct the texture for the windows or the sides of the house. But if you want to try using Unwrap UVW to do so, or if you are simply curious how it was done for the completed model, here are the mappings used.

NoteThe completed model has some additional mapping corrections not shown here: the bottom of the lintel and the bottom of the eaves. You can investigate these, if you wish, by looking at facade_modeling_04.max or facade_modeling_completed.max.

Windows

Mapping for the windowsills

Mapping for the window jambs

(The same texture is used for both sides of the windows.)

House Sides

Left side

Right side

Next

Modeling the Second House