A Preliminary 2D Ray Tracing Demo for Spherical Mirrors in Excel

April 30, 2011

This is a demonstrative model for 2D spherical mirror ray tracing in Excel. It works in Excel 2003 at about 40 frames per second and in Excel 2007 at about 4 frames per second. You can start it in  a hands-off demo mode by clicking the “Fully Automatic Demo” button and at any time you can hit the the “Demo Style” button to choose a flexible (pulsating) mirror or a…


Introduction to Geometrical Optics – a 2D ray tracing Excel model for spherical mirrors – Part 3

April 28, 2011

This section explains explains how to implement the formulas that define the emergent (reflected) rays into a custom VBA function. Though geometrically the last two presentation might look a little  elaborate, just be patient and follow the presentation, or even better try to just sneak peek and do it yourself. All this derivation is done based on first principles and some Mickey Mouse geometry. Take all the time you need, a day, a week…


Introduction to Geometrical Optics – a 2D ray tracing Excel model for spherical mirrors – Part 2

April 27, 2011

This section explains the illumination setup by using an artificial star, derives the equations of the incident rays and also solves the system of equations for finding the exact coordinates of the points where the incident rays hit the mirror. Looking at the sign of the determinant of a quadratic equation involved in finding the intersection between an incoming ray and the mirror we can say if the ray hits…


A Solver for Systems of Linear Equations in Excel

April 25, 2011

This is a linear system of equations solver in Excel. The size of the system is programmable by the user from 2 to 20 which means, depending on the setting selection, the model can instantly find the solution of linear systems starting from 2 equations and 2 unknowns up to 20 equations and 20 unknowns. It uses the following built-in Excel spreadsheet functions: MMULT(), MINVERSE() and TRANSPOSE(). Like everything on…


Flight Simulator Tutorial #7 – upgrading the joystick chart, adding a reset button and a throttle scroll bar

April 22, 2011

This section displays the landscape on a 2D scatter chart and also upgrades the joystick chart by adding a dial behind the joystick image. This technique of using a stack of a back chart to display dial sprites and a front chart with transparent background to display various control devices, indicator needles and text will extensivly be used in this and future models.


Flight Simulator Tutorial #6 – macro review, scene derivation and integration, mapping of the 2D u-v data into a chartable 1D array, rejecting image artifacts

April 21, 2011

This section finishes the macro analysis and continues with the conversion of the u-v 2D formula array into a chartable 1D array. It also adds two columns to the chartable array, a masking condition for each triangle and masked u-coordinate which will throw out of the visible portion of the chart any shape which has a minimum of one vertex behind the virtual pilot. The section also explains the phenomenon…


Flight Simulator Tutorial #5 – the worksheet implementation of the perspective handling formulas and VBA the macros

April 20, 2011

This section explains the spreadsheet  implementation of the perspective rotation and translation formulas within the Present array and also the implementation of the 3D-2D conversion formulas within the Past array, then it goes on to presenting the VBA macros used (the Reset and JoyStick macros). The PDF and XLF files were updated -04/22/2011, 5:20 pm MST.


A First Flight Simulator Model in Excel

April 18, 2011

This is the first version of a 3D flight simulator in Excel. Start by adjusting the zoom on your file to fit the screen, so you can see the whole chart and the buttons underneath, then click “Reset” and then click the red dot in the center of the joystick. After that, the joystick handle will “stick” to your mouse pointer so your mouse becomes the airplane control. Back and forth mouse…


TRANSPOSE() & MMULT() – two important Excel spreadsheet functions for matrix manipulations

April 11, 2011

This is a tutorial introducing two important matrix manipulation spreadsheet functions in Excel: the matrix transposition function TRANSPOSE() and the matrix multiplication function MMULT(). These functions are a bit harder to use than the regular spreadsheet functions in the sense that the result is a matrix and a matrix cell range is treated by the program as a unity (you cannot change the formula since you cannot operate on a single cell). There are some…


Flight Simulator Tutorial #1 – the joystick and a ground mesh

April 9, 2011

This is the first section of a tutorial explaining how to build a 3D flight simulator in Excel. This part deals with creating a joystick and a triangular ground mesh. The joystick model was explained in a previous post from January 2011 and the ground mesh was already used in the 3D roller-coaster. Please be aware that both the PDF and Excel files for this section have been updated on 4/13/2011 at 7:15 pm. 


Spectral Analysis – a Fourier transform tutorial – part #5

April 8, 2011

This part of the tutorial demonstrates the Fourier transform operation in a few cases of periodic and aperiodic signals, such as an AM signal, an FM signal, a rectangular nonrepetitive signal and a cardinal sinus signal. The last slide contains an application to the scaling property of the Fourier transform on a nonrepetitive time signal. It actually shows that spreading a signal in the time domain shrinks its spectrum and…