# Monthly Archives: December 2019

## Make an improved diagonal picture montage in C#

My earlier example Make a Pinterest-style diagonal picture montage in C# showed how you could make a picture montage showing parts of images rotated by a desired angle. While using that program today I found a small bug. The areas … Continue reading

Posted in drawing, graphics, image processing, tools | | 1 Comment

## Use VBA to randomize Excel selections

The post Use VBA to randomize cells in Excel explains how you can randomize a simple selection’s rows. Unfortunately that method cannot randomize Excel selections in general. In particular it doesn’t work if the current selection includes multiple areas on … Continue reading

Posted in Excel, VBA | | Comments Off on Use VBA to randomize Excel selections

## Understand range areas in Excel VBA

Most of my VBA examples assume that the current selection is a single block of cells. If the selection includes a single area, then you can easily loop through the cells that it contains. Unfortunately if the selection includes multiple … Continue reading

Posted in Excel, VBA | | 1 Comment

## Let the user draw rotated skewed polygons in C#

The example Let the user draw rotated polygons with right angles in C# draws polygons with edges that are parallel or perpendicular to a baseline. This example is very similar except its polygons have edges that are parallel to one … Continue reading

Posted in algorithms, drawing, graphics, mathematics, transformations | | Comments Off on Let the user draw rotated skewed polygons in C#

## Let the user draw rotated polygons with right angles in C#

This example lets the user draw rotated polygons where all edges are either parallel or perpendicular to a defined baseline direction. As a result, all of the polygon’s angles are right angles. (And yes, I know that the polygons aren’t … Continue reading

Posted in algorithms, drawing, graphics, mathematics, transformations | | Comments Off on Let the user draw rotated polygons with right angles in C#

## Let the user save an image of a smooth curve in C#

The post Let the user draw a smooth curve in C# shows how you can let the user draw a smooth curve. This example extends that one to let you save the curve in an image file. There are a … Continue reading

Posted in drawing, graphics | | Comments Off on Let the user save an image of a smooth curve in C#