Mandelbulb3D/Reference/Position and Rotation
Position and Rotation
[edit | edit source]Camera position and rotation can be controlled and monitored in the Position and Rotation panes at the top of the Side Panel. These fields accept direct input from the computer keyboard, and can also be changed through the Bottom Toolbar controls and the Navigator window.
The Navigator window is the primary tool for adjusting camera position and rotation. The Position and Rotation values in the Side Panel show the numerical results of data sent from the Navigator window's View to Main button.
The controls in the Bottom Toolbar adjust Position and Rotation, but the results can't be displayed until the Calculate 3D button is clicked and the fractal is re-rendered.
Position
[edit | edit source]Values in the Position pane are unlike those in traditional 3D graphics. The primary coordinate system in a game engine, CAD program, animation package, etc. is global or world coordinates. The camera is an object situated within the virtual world. In Mandelbulb3D, the coordinate system is local to the camera. The visible part of the virtual world is an extension of the camera. Camera position, zoom, and clipping planes all work differently to traditional 3D graphics.
X Mid and Y Mid
[edit | edit source]In Mandelbulb3D, the volume of space that's calculated by the distance estimation engine is the same volume of space that's visible to the camera. X Mid and Y Mid set the midpoint for distance estimation, also setting the virtual world's horizontal and vertical position in the picture frame. Changing X Mid or Y Mid chooses a different point in the world as the center of the picture plane.
Z Mid, Z Start, and Z End
[edit | edit source]The Z mid value centers the calculations in the third dimension, the distance from the camera. This also sets the distance of sharp focus for Depth of Field renderings.
The Z Start value sets the near clipping plane for the distance estimation engine. Surfaces closer than the Z start value do not render. If the Z Start value is greater than the distance to a surface, the fractal form is cropped.
The Z End value sets the far clipping plane for distance estimation. Geometry at a distance greater than Z End is not rendered.
The buttons labeled Z Mid, Z Start, and Z End render a 2D slice through the fractal shape. Click one of these buttons to render a slice at the distance of the Z midpoint, near clipping, or far clipping plane.
Z Start and Z End also determine the start and end distances for Depth Fog in the Lighting Panel's Ambient tab.
Z End can be adjusted interactively with the Navigator window keyboard shortcuts F1 and F2.
Get Midpoint
[edit | edit source]Get Midpoint allows re-centering the frame. Click the Get Midpoint button, then click the image to re-frame the shot. The location you click is moved to the center of the frame. Click Calculate3D to see the new framing.
Reset
[edit | edit source]Reset inserts pre-determined values for the Position parameters. However, these are not the same values as the Mandelbulb3D default startup conditions. The Reset button sets the Zoom to 0.8, and rotation angles to approximately zero. This produces a top-down view of the scene. See the section on Rotation below.
Zoom
[edit | edit source]The Zoom value is not like the zoom or focal length on a camera, it's actually more like a dolly. The field of view or angle of view is controlled in the Camera tab. The Zoom parameter scales the picture plane at the Z Start position. This gives the visual effect of moving the camera forward or backward.
The Navigator window can change the Zoom value, automatically or manually. Zoom is a parameter separate from camera movement. And yet, the effect of Zoom is just like a camera dolly, not like field of view. Zoom and camera position combine and interact, resulting in the effective camera position. This leads to some confusion, especially because the hidden parameter Fixed Zoom And Steps is disabled by default. When it's disabled, camera movements in the Navigator cause the Zoom to adjust automatically, with unexpected results. The recommended usage is to enable Fixed Zoom And Steps, then move the camera. If the near portion of the fractal shape is clipped, dolly the camera backward and then set the Zoom parameter to a higher value.
Rotation
[edit | edit source]To change the scene rotation, enter values in degrees into the X, Y, or Z fields. Click the Apply To Image button, then click the Calculate 3D button.
Rotations in Mandelbulb3d are also different from standard 3D graphics programs. Setting rotations in these fields is counter-intuitive. The Navigator window is a better way to set camera angles. For reference, the following rotation values will produce traditional perspective views from the six cardinal directions of 3D space.
View | X rotation | Y rotation | Z rotation |
---|---|---|---|
Top | 0 | 0 | 0 |
Front | -90 | 0 | 0 |
Back | -90 | 0 | 180 |
Right | 90 | 180 | -90 |
Left | -90 | 0 | -90 |
Bottom | 180 | 0 | 0 |
Reset 0
[edit | edit source]The Reset 0 button sets all rotation values to zero, resulting in a view from the top. It does not restore the scene default values. In a new scene, Y and Z have values of zero, but X has a value of -40 degrees.