All mathematics is devilry as far as I’m concerned, though numeric rituals are rarely as explicit as in The Devil’s Calculator. Made by the fella behind word puzzler Synonymy, The Devil’s Calculator is about solving equations backwards on a spoOoky graphing calculator to reach the number 666. The satan in the calculator has scrambled the functions of logical operators, see, so we need to… look, I live a chaste life free of algebra so I didn’t even know the game’s symbols were fake. These runes look as real to me as A† or ≜ or A⊗B or any other ‘real’ symbol I had to Google and must now flush out my brain with a neti pot of holy water. “An evil calculator has its normal arithmetic operators replaced with sadistically obscure functions,” developer Christopher Cinq-Mars Jarvis explains. All calculators are evil and all numbertricks are sadistic, of course, but I get what he’s saying. “Using logic and … [Read more...] about Do maths to thwarts satans in The Devil’s Calculator

# Immediate needs annuity calculator

## Calculating Damage from from object collision

I need to calculate the damage resulting from a crash of two objects. I found the formula of the resulting kinetic energy: E = m * v² / 2 I guess I also have to use the masses or sizes of the objects as well. It will make a difference if the spaceship collides with a mountain (which certainly will make both of them dealing heavy damage), or the spaceship is colliding with a floating tennisball in which case neither of them are dealing damage. … [Read more...] about Calculating Damage from from object collision

## Calculating pitch angle to hit a target using a projectile that has fixed speed

I am trying to calculate a vertical angle needed to hit a target at [distance, elevation] 2D coordinates relative to shooter given a fixed projectile velocity, air drag and gravitational acceleration. Although I operate in 3D world (minecraft) the task itself eliminates the 3D problem. Once you calculate the rotation around your axis, which is in my case just atan2(-x3D, -z3D) what I'm solving is described on this picture: From a wikipedia article about balistics I have picked this equation. As you can see, it seems to directly solve for my angle: $$ \theta = arctan \bigg( \frac{v^2 \pm \sqrt{v^4-g(gx^2+2yv^2)}}{gx} \bigg) $$ So I rewrote the equation in javascript as Math.atan((v*v+Math.sqrt(v*v*v*v - g*(g*x*x+2*y*v*v)))/g*x); where v is speed, g is gravitational acceleration, x is distance and y is elevation of the target. I implemented the whole algorithm as following: //Assumed constants var g = 9.81; //Gravitational acceleration var v = 35.9; //Experimantally measured arrow … [Read more...] about Calculating pitch angle to hit a target using a projectile that has fixed speed

## Get the mesh Project Plane on Click and calculate its area

Here is the excerpt of my script which is calculating the surface area and face area of a mesh on OnMouseDown Event. private void OnMouseDown() { Mesh selectedMesh = this.gameObject.GetComponent<MeshFilter>().mesh; float surfaceArea = CalculateSurfaceArea(selectedMesh); float areaFromXFace = CalculateFacingArea(selectedMesh, new Vector3(1, 0, 0)); float areaFromYFace = CalculateFacingArea(selectedMesh, new Vector3(0, 1, 0)); float areaFromZFace = CalculateFacingArea(selectedMesh, new Vector3(0, 0, 1)); float areaFromClickedFace = ProjectionPlaneClickedArea(selectedMesh); string areas = "\n Surface Area : " + surfaceArea; areas += "\n Area From X-axis Face : " + areaFromXFace; areas += "\n Area From Y-axis Face : " + areaFromYFace; areas += "\n Area From Z-axis Face : " + areaFromZFace; areas += "\n Area From Selected Face : " + areaFromClickedFace; Debug.Log("Areas :"+ areas); } float ProjectionPlaneClickedArea(Mesh selcectedMesh) { Camera c = Camera.main; … [Read more...] about Get the mesh Project Plane on Click and calculate its area

## Players figured out a way of calculating PS4 game sales figures through Trophy data, Sony emails

By using Trophy data, and promotional emails Sony has been sending to PS4 owners, players managed to approximate the number of copies certain games have sold. PS4 Trophy data is public, of course. Anyone can easily access the Trophy list for a game they own, and Sony will show what percentage of players have obtained each one. That’s why we have the ultra rare, and rare categories, with Platinums being the most rare across the board. This isn’t new, and many used it in the past to gauge how far players have gotten into a game, how many reached a certain level – or even play a certain mode. But where it gets interesting is through My PS4 Life. These emails are automatically sent to PS4 players, and they contain more valuable data than you might immediately assume. The emails include fancy graphs covering personal stats compared against the rest of the player base. One data point in particular is the number of players who obtained a Trophy. When used in conjunction … [Read more...] about Players figured out a way of calculating PS4 game sales figures through Trophy data, Sony emails