Monthly Archives: November 2015

Platonic Solids Part 5: Cube and octahedron

Posted on November 30, 2015 by RodStephens

You may recall from the first article in this series (Platonic Solids Part 1: What are the Platonic solids?) that each platonic solid has a dual. The cube and octahedron are duals of each other. To make a dual from … Continue reading →

Posted in algorithms, graphics, mathematics, wpf | Tagged 3D, algorithms, C#, C# programming, cube, dodecahedron, duals, example, example program, graphics, hexahedron, icosahedron, mathematics, octahedron, polytopes, regular polytopes, regular solids, tetrahedron, Windows Forms programming, WPF | Leave a comment

Platonic Solids Part 4: The octahedron

Posted on November 30, 2015 by RodStephens

Finding the Octahedron’s Vertices A platonic octahedron has six triangular faces. Because the edges of the triangles all have the same length, the triangles are equilateral triangles. If an equilateral triangle has edges of length 1, then its height is … Continue reading →

Posted in algorithms, graphics, mathematics, wpf | Tagged 3D, algorithms, C#, C# programming, cube, dodecahedron, example, example program, graphics, hexahedron, icosahedron, mathematics, octahedron, polytopes, regular polytopes, regular solids, tetrahedron, Windows Forms programming, WPF | Leave a comment

Platonic Solids Part 3: The cube

Posted on November 29, 2015 by RodStephens

A platonic cube has six square faces. The cube’s symmetry makes it easy to find the coordinates of its vertices. For a cube with edge lengths of 1, the vertex coordinates are (±0.5, ±0.5, ±0.5) as shown in Figure 1. … Continue reading →

Platonic Solids Part 2: The tetrahedron

Posted on November 28, 2015 by Rod Stephens

A tetrahedron has four faces that are equilateral triangles. In an equilateral triangle, the sides have the same lengths and they meet at 60 degree angles. Figure 1 shows a tetrahedron. Finding the Tetrahedron’s Vertices It is a trigonometric fact … Continue reading →

Platonic Solids Part 1: What are the Platonic solids?

Posted on November 28, 2015 by Rod Stephens

This is the first in a series of posts about the Platonic solids. These posts will show how to find the corners of six Platonic solids: tetrahedron, cube (hexahedron), octahedron, dodecahedron, and icosahedron. Deriving these values requires only algebra and … Continue reading →

Posted in algorithms, graphics, mathematics, wpf | Tagged 3D, algorithms, C#, C# programming, cube, dodecahedron, dual, dual solids, example, example program, geometry, graphics, hexahedron, icosahedron, mathematics, octahedron, platonic solids, polygon, polytope, polytopes, regular polygon, regular polytopes, regular solids, solids, tetrahedron, Windows Forms programming, WPF | 2 Comments

Add and remove pictures in an Excel worksheet

Posted on November 24, 2015 by Rod Stephens

This is another brief foray into VBA programming. When you click the Insert Image button, the following VBA code executes. ‘ Insert a picture at the selection. Sub Button1_Click() Dim filters As String Dim filename As Variant ‘ Define the … Continue reading →

Posted in Excel, Office, VBA | Tagged example, example program, Excel, insert picture, Microsoft Office, Office, remove picture, VBA, Visual Basic for Applications, Windows Forms programming | Leave a comment

Number files in a directory in C#

Posted on November 24, 2015 by RodStephens

I recently went on a trip where I took almost a thousand pictures. My phone (which has a pretty good camera) gives the pictures file names such as WP_20151106_22_04_47_Pro.jpg. I wanted an easy way to number files so they have … Continue reading →

Posted in directories, files, system | Tagged C#, C# programming, directories, example, example program, files, number files, rename files, system, Windows Forms programming | Leave a comment

Convert a directory’s files to grayscale in C#

Posted on November 23, 2015 by Rod Stephens

The example Quickly convert an image to grayscale in C# explains how to convert an image to grayscale. This program uses the same technique to convert all of the files in a directory to grayscale. (I needed this to prepare … Continue reading →

Posted in files, graphics, image processing | Tagged C#, C# programming, color, convert to grayscale, convert to greyscale, example, example program, files, graphics, grayscale, greyscale, image processing, Windows Forms programming | Leave a comment

Perform line clipping in C#

Posted on November 22, 2015 by Rod Stephens

The example Perform line trimming in C# shows how to determine what the DrawString method does when the last line of text doesn’t fit horizontally in a formatting rectangle. This example shows how to perform line clipping when the last … Continue reading →

Posted in drawing, fonts, graphics | Tagged C#, C# programming, clipping, drawing, example, example program, fonts, FormatFlags, graphics, line clipping, line limit, StringFormatFlags, text clipping, Windows Forms programming | 1 Comment

Perform line trimming in C#

Posted on November 19, 2015 by Rod Stephens

Line trimming lets you determine how drawn text ends when it reaches the end of the available space. For example, the text could stop in the middle of a word or it could stop after the last word that fits … Continue reading →