The sizing of a plant on the plan is a bit of a ticklish subject. Punch! uses an algorithm which is designed to show the plant growing exponentially over time until it reaches it's maximum height. Normal plant growth is not exponential; it is generally linear (for height) but is non-linear near the low and high ends of the growth range, forming an "S" curve, as it is known to biologists. In addition, the Punch! algorithm has an error in it (based on what is stated in the description of plant growth in the Punch! Developer's Kit), and an inspection of a plant's growth shows that the error is likely embedded into the actual Punch! growth formula. Finally, growth is predicated on the tallness of the picture frame, not on the image in the picture, which is, in some cases, quite different.
All that being said, the plant's "grown" using Punch! are well within the normal biological variability and the differences are seldom noticed by users, who are looking more for the plant's effect than a real idea of what plant growth will produce, so all of our harping on it here is mere comment. The reason we bring it up is that our plant tracks are, on the whole, smaller than Punch!'s, a size that we think is more appropriate for the plants on the plan.
This picture shows a series of Austrian pines placed on a plan using Punch!. The plant age slider is set at the default value of 18, which means a base age of 15 years old. The individual tree ages are, from left to right, 0 through 5 additional years (the ages are intended to be added to get the projected age of each tree), so the trees should range from 15 through 20 years old. The trees are arranged so that the symbols are just touching, with a small wall between each symbol.
Notice, first of all, how the size jumps from the first image to the second. This is due to a three year addition made to adjust for the fact that the first three slider growth stages are in 1/4 years rather than years. However, the adjustment is made to the wrong variable, and in the wrong direction! That causes a large growth spurt between individual age 0 and 1 years, regardless of the slider value. Secondly, notice how small the trees are, side-to-side, as compared to the actual tree width shown in the LiveView picture. This is due to the fact that the trees are much thinner then the nominal 85% of the height that the Punch! algorithm allows for. At the bottom of the picture is the equivalent tree sizes expressed by PlantTracks; as you can see they are significantly smaller than the equivalent Punch! symbols, and we think they more appropriately capture the way the plants look in massed groups.
PlantTracks gives the user additional control over the symbol sizes. The first option is labelled Standard Punch! size (based on age), and is the default size selection. This uses Punch!'s ageing algorithm (with the error mentioned above eliminated). This will result in somewhat smaller symbols than Punch! on the average, but correctly "grown".
The next option is Based on Max Ht only. This presents symbols assuming all the plants have matured and reached their full growths.
Std corrected for pic dimensions - this option creates an aged tree size, and then cuts it down by comparing the width and height of the image on the plant sample. This gives the radius that most closely matches the plants' corrected rendered size to the symbol.
Fixed width - this option opens a window in which to enter a measurement for the plant's diameter in inches or millimeters, as appropriate.
Finally, the last, non-radio-buttoned option is labeled "Additional setting for all types", with an entry box. It gives a final percentage change that can be made to the plant scheme. It is set by default to 100%.
All these options are, of course, available on a scheme basis. The scheme can then be applied to one plant, all the plants or any combination of them, as desired.
PlantTracks and the contents of this help file are
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