## General Usage

Ivy Grower is a Cinema 4D tool. It will remain active as long as another tool is not selected. Settings and current information are retained between selections of other non-tool elements that show their information in the Attributes Manager. Configuration settings on both the Growth and Birth tabs are automatically stored to Cinema 4D's preferences and reloaded when the tool is reactivated or a new session of Cinema 4D is started so that you never need worry about conscientiously retaining the settings in these situations.

Ivy Grower will grow ivy on any object that is either already polygonal or would become polygonal when using Make Editable or Current State to Object. The latter type includes most geometric primitives (Cube, Sphere, Landscape) and generators that generate polygons (Sweep NURBS).

As always, it is highly recommended to save your document prior to using this plugin and between creation of new ivys. If you encounter crashing during the growth process, the most likely culprit will be a Timer setting that is too low for your processor or in conjunction with other processes which is not allowing the new branches to be added to memory in a reasonable time. Also be aware that ivy geometry created from many living branches can consume memory quickly - monitor your memory when pushing the envelope!

The process:

The object on which the ivy is to be grown should be selected in the Object Manager. You can select a new object while the tool is active but you will need to reselect the tool or select Tool under the A.M. Mode menu to show its information in the Attributes Manager. Remember that if you want ivy to grow over several objects even though you selected one to receive the seed point, the best approach is to group them under a Null object and select the Null object. Ivy Grower converts this using 'Current State to Object' to get a polygonal representation. Unfortunately, polygonizing the entire document has proven erratic.

After activating the tool, you will need to create a seed point on the object where the ivy will start growing just as in Ivy Generator. Double-click to determine the seed point. You can change the Seed Point Color of the displayed point before selecting one under the Growth tab in the Display Colors section.

Growth

Once you have a seed point, click on the Grow Ivy button to start growing the ivy skeleton on which the ivy geometry will be based. You'll note two things when the Grow Ivy button is clicked. First, the button now shows Stop Growing as an extra indication that the growth process in ongoing. Second, the text to the right of the button shows the number of Living Branches. Clicking the button again stops the growing process. If you click the button another time, growth will continue from where it left off. To abort the previous growth and start a new growth at the same seed point, you can Ungrow and then Grow Ivy anew. Note that you can navigate about the scene with the camera tools while growth is in progress. Since the growing process isn't in a separate thread, growth will hesitate as you navigate and resume once you finish navigating. Again, the two colors, Growth Branch Color and Adhesion Vector Color, of the ivy skeleton can be changed to suit the situation.

If you would like to have the ivy grow with respect to a guiding spline, drag and drop a Spline object or primitive from the Object Manager into the Spline linkbox under Growth's Follow Spline section. Set the amount of influence the spline has on growth with the Strength value. Note that you still need a polygon object to receive the seed point!

Note: Invert Normals was added so that you need not concern yourself about converting procedural into polygon object and preparing the polygon normal direction in advance. This option inverts the normals of the internal polygon object copy used by the growth process so that you can, for instance, grow ivy inside a primitive Sphere object without any of the hassle (beyond enabling this option).

Birth

If you are satisfied with the growth you can then go to the Birth tab and turn the skeleton into textured polygonal geometry or branch splines. Don't fret! If the result is not what you expected, simply change the Birth settings and maps and hit Birth again to redo the geometry and spline creation. Realize that the more living branches there are the more polygons and memory used when giving birth. There are three types of birth options: Create Polygon Mesh, Create Branch Spline, and Create IGSpline. Any or all of these can be enabled in the same birthing process. This allows multiple representations to be made simultaneously.

When creating polygonal geometry with Create Polygon Mesh enabled, you can opt to have the branches, young leaves, and adult leaves separated into three polygon objects by enabling Separate Branch/Leaf Objects. As can be seen on the Birth tab, you can select the texture maps used for each part of the ivy: adult leaves, young leaves, and branches. A preview of the resulting Cinema 4D material shows you what the materials will look like before birth. For now, this automatically sets the Color and Alpha channels for the leaves and the Color and Bump channels for the branches using these texture maps. If you are using the R11.5 build of Ivy Grower, you can opt to make Render Instances instead of a polygon mesh for your ivy leaves by enabling the Render Instance for Leaves checkbox.

It is also possible to create a spline representation of the branches by enabling Create Branch Spline. Additionally, you can opt to create a special-purpose IGSpline for branch growth emulation by enabling Create IGSpline. Each of these spline options also includes the ability to create a Sweep NURBS representation with the help of a cross-section spline added to the accompanying linkbox.

To start a new ivy plant, simply restart the process. If you are growing several ivys on the same object, you do not need to select it each time.