GMU:Einführung ins Programmieren mit Processing/Seminar: Difference between revisions

GMU:Einführung ins Programmieren mit Processing/Seminar (view source)

Revision as of 12:18, 10 November 2011

1,933 bytes added , 10 November 2011

→‎cobblestone

Md

94

edits

@@ Line 233: / Line 233: @@
 Due to the irregularities in the stone's sizes a random component is added to the pattern, making it harder to decode while still keeping it repetitive.
+'''Pattern definition''':
+[[Image:Md-processing-cs-1.png|thumb|cobblestone pattern]]
+The pattern consists of basically one shape, a square.
+The squares are arranged in rows and columns as shown in the image on the right (one row highlighted in green, the two columns separated in red). The tricky part is that within each row/column the stones are placed along an arc while being rotated according to their position on the arc.
+The radius of the arc is determined by the size, number and spacing of the squares used to form one row/column segment of the pattern and will stay the same during the whole drawing process. The position of each square on an arc is determined by its width and the predefined spacing. The orientation of each square is determined by its position on the arc, starting with -45 degrees and being rotated clockwise by 90/(n-1) degrees (where n is number of squares on each arc; this is also the angle between the centers of two stones on the arc).
+The pattern can be drawn with three nested loops:
+* ONE looping through each row, setting the center Y for the arc's circle (starting with the position of the square closest to the bottom (highest value) plus the radius and being decreased by the square's height and predefined vertical spacing during each run)
+** TWO looping through each column, setting the center X for the arc's circle (starting with the of distance of the leftmost square to the center of the arc's circle and increasing it by two times that distance during each run)
+*** THREE looping through each stone, going along the arc in previously determined steps and placing a square in it's proper rotation (-45 degrees incremented by the length of the step during each run).
+Each stone shall of course be drawn only if inside the pattern's bounding box and the first stone of each column is only drawn for the first column as it is the same as the last stone for all following columns.
 (md)
 === Growing Ivy ===