Perspective_tut

Perspective and Depth

Achieving a sense of perspective and depth in your ZBrush scenes is different than traditional 3D programs. The user does not place a camera in a scene to view the objects; rather the objects are placed to represent the camera angle. As with 2D painting, more is required of the artist to get a proper sense of perspective. ZBrush does have features that help with this task and there are tricks that the artist can do as well. This tutorial will illustrate some or these techniques.

When you draw an object on screen to model and enter edit mode, it appears in an orthogonal display.

You can give the object perspective by Turing on that feature located in the draw panel.

To see this, you must go in the translate panel, turn off edit object (T) and enter one of the transform modes, move, rotate, or scale. Then you can click on the Perspective button and adjust the slider to get more or less of it.

When you move an object around the screen in this mode, it stays in the same angle.

However, if your SHIFT press the Perspective button you go into a global perspective mode, and when you move the object around the screen you can see it adjust. You can push an object away or towards the “camera” as well while in this mode. Once you go back into edit mode, the object will switch back into orthogonal view, but you can go into the perspective view at any time, or turn it off completely.

Pillar Hall

This section will demonstrate the creation of a large room of pillars and the techniques to achieve perspective and scale.

A cube3D is drawn on screen and put in edit mode. Polyframe mode is turned on. Then most of the object is masked except for one side and the first row of faces.

In the Selection panel, hide unmasked is press. This will hide or make invisible the unselected faces.

In the modifiers panel, double sided is turned off

In the same panel, the flip button is pressed, which will flip the faces. Global perspective is turned on and the object is rotated. This is used to create the walls of the room. Polyframe mode is left on for now to help as a grid for lining up the objects to come in the scene.

The object is sized on the Z and X axis and positioned. Here is where the camera angle or viewpoint is established. A marker was made for this object.

A pillar object is made out of a sweep profile primitive. A marble texture is applied to it, and it is positioned in the scene in a new layer while in Global perspective mode. The settings are left the same from the cube object.

The pillar is then duplicated through the snapshot feature, each one being brought forward. The texture has the right scale as the object is brought forward due to the global perspective.

This is repeated for 2 more rows of pillars. The polyframe display of the Cube helps with the positioning.

On a new layer, the marker is used to replace the cube or room object. This time, polyframe is turned off. The object is divided a couple of times. This is because it will not be displayed in smooth mode, and there need to be a little more resolution to appear smoother. The reason it is not in smooth mode is that it will round the edges of the room too much for something of this scale.

While the object is still “live” (not dropped to the canvas) a stone texture is applied to it. The H and V repeat are adjusted to give a scale too. The pattern of the texture also helps to give a sense of perspective because of the lines it creates. The eye can follow these visual clues.

To give a more definite reference of scale, a door is placed in the far wall. This is a cube 3D drawn in Zsub mode to cut into the wall. It is hopefully assumed by the viewer that his door is for humans, and therefore this is another clue as to the size of the room.

A few accoutrements are place around the doorway.

Now that the objects are in place, the lighting can be worked on. The role and value lighting plays in depth and perspective should not be overlooked. First, the main key light is placed.

For visual interest and also to help with perceptive, several yellowish point lights are at various spots between the pillars down the length of the room. The further the light is from the front of the scene, the dimmer it is made. At this stage, any repeating patterns on the pillars are painted over to lessen them.

The pillars and the room objects are made with different materials. This is so they can be adjusted independently. The diffuse value and diffuse curve can be used to separate the two. In this case, the pillars can be brighter or darker to stand out from the walls.

Once the lighting is complete, the layers are baked, but still kept separate for ease of editing. The lighting phase can continue with the shading enhancer brush. It can be used to darken or lighten choice locations of the scene. Here it was used to darken the corners of the room, and draw your eye towards the doorway, which was also shaded.

The shading enhancer brush was also used to subtly darken the pillars that are further away.

Fog can also be used for depth. It is an obvious choice for this, but should be used judiciously since it does tend to mute or wash out the colors. In this scene, it can be used, with a black color, to darken the back of the room. The intensity curve and the value were adjusted to keep the fog at the back.

Idol Field

The pillar hall example had strong geometry and textures to aid in the perspective. What do you do with an organic outdoor scene where there aren’t any geometric lines to guide the eye?

This example will use some of the techniques of the previous, and introduce some more.

A landscape is created with the Plane 3D, viewed in Polyframe mode, and positioned in global perspective mode. A marker is made.

Three stone idol objects are placed in the scene on a new layer at various distances. They are positioned in global perspective mode as well.

The ground plane is placed back in the scene using the marker. A simple texture is applied while the object is still in edit mode.

The elements are set, now the details need to be added. The stone idols do not look very much like stone, so the material modifiers are changed to rectify this. The noise, noise radius and color bump are adjusted to get a rock like texture.

But when the other 2, farther idols are viewed, the texture doesn’t look right. This is because the materials don’t take in account for depth.

Since the other idols are farther away, their texture will not be as pronounced. The trick here is to save out the first stone material, and then load it back into another unused material channel. A brush is set to just apply material, and the next idol is painted with the material. Now, the settings can be adjusted without affecting the first idol. The bump is turned down, as well as the noise radius to simulate the smaller detail.

The same process is done to the farthest idol, which should have the least amount of detail visible.

Details are also hand painted. Again, the distances of the objects are kept in mind.

Now, the lighting is worked on to simulate daylight. Another material modifier than can help with a sense of distance is the diffuse and diffuse curve. The farthest idol is given lighter shadows through these settings, while the nearest idol’s shadows are darker. This will help push the farthest idol in the distance. A background sky tone is placed on another layer with the flat material. The layers are baked to set the lighting.

The field can use a little more life than the texture map supplies. Grass would be a great feature, and the fiber brush will create this nicely.

The fiber brush settings are adjusted to pull color from the source, and some grass is drawn. Unfortunately, the fiber brush does not obey any depth in the scene.

It is up to us to adjust the settings as we paint the grass. Naturally, the grass will appear smaller in the distance, so the first rows of grass are painted with a small brush size.

The fiber brush size is gradually increased as well as the color brightened as the grass is painted over the scene. The fiber size is also thickened a small amount to make the blades in the foreground larger. Lastly, the shading enhancer brush is used to punch up areas. The Gods are now appeased.

As you can see, a combination of techniques should be used to give your scenes depth and perspective. Depth of field is another useful feature. This can be found in the render panel, and is easy to set up.

You can also blur background objects with the blur brush for added effect.

When using perspective, even a simple Zspheres object can be turned into an ominous tunnel. This was created by flipping the faces of the object moving it into position in global perspective mode.

Another way to arrange items in a scene is to set them up in an easier orthographic view. Place each item, and make a marker for it. Then, press multimaker and you’ll have one object that you can rotate as a whole and further arrange the objects.

You won’t be able to see perspective until you turn it into a polymesh object. Then, you can view all the objects together in any perspective.

Don’t forget that you can texture the objects first before making a multimarker. That way, they will retain all these materials and textures when a polymesh is made. The downside is that you cannot move the individual items at this stage.