Modern Coordinate Modification and Verification System (MCMVS)

Modern Coordinate Modification and Verification System (MCMVS) is a modern rewrite of the Coordinate Modification and Verification System (CMVS) written by my dad from 1988 to 1993.

The original version was written in C for the DOS operating system, and leveraged the graphics mode of DOS to visualize 3D points and lines.

My version, MCMVS, is written in C using SDL2.

MCMVS Features

• Renders 3D splines in orthographic view
• Moves splines across X and Y axis with trackpad scroll or WASD keys
• Zooms in and out of splines with SHIFT + trackpad scroll
• Rotates splines in 3D space with SHIFT + trackpad or IJKLUO keys
• Mirror splines across Y axis plane with m key
• Show original spline vectors with p key
• Show X, Y, and Z views of object with x, y, and z keys

CMVS Features

• Simulaneously rendered 3D splines in X, Y, Z, and orthographic views
• Allowed the user to rotate the splines in 3D space by entering specific theta and phi values
• Allowed the user to move the splines in 3D space by entering specific X, Y, and Z values
• Allowed the user to zoom in and out of the splines in 3D space by entering specific zoom values
• Could show the user the X, Y, and Z values of a specific point
• Allowed mirroring of splines across either the X, Y, or Z axis with a user-specified offset
• Could color specific splines
• Create, erase, and edit specific vectors inside a spline
• Import/Export/Translation of .DAT files to Drawing Exchange Format(DXF) and Initial Graphics Exchange Specification(IGES) files
• Plotting of splines onto a printer communicating over a parallel port using HPGL
• Icon buttons with 3D effects and shading drawn in program
• Korean/English language support with a custom vector font for Korean characters
• Saving screen buffer areas that are overlapped when opening a button submenu to redraw when the submenu is closed

Technical Details

• A .DAT file contains splines made up of 3D point coordinates in XYZ space. When the program reads the .DAT file, it stores each spline into an array of splines.
• A deeper explanation of the array of splines is a 2D array of pointers to spline arrays, where each spline array is an array of pointers to vectors.
• The program then renders the splines in 3D space, and allows the user to rotate, move, and zoom the splines in 3D space.
• To apply rotations, each vector in the spline undergoes a rotation matrix transformation. The rotation matrix is calculated using the theta, phi, and psi values modified by the user.