Actionscript 3 :: Mathematical Error In Physics Restitution Formula
Aug 14, 2011
I admit it. I'm a mathematical imbecile. should I be attempting this at home? Probably not without serious injury. Anyway. Anyone that has a bit of experience in games and physics who can review this code and provide insight into why there is a built in "loss" in velocity in prototype would be hugely admired.
the concept: the actor falls from the sky, at some point intersects a boundary (trampoline.y) after which gravity (in this example a value of 1.6) stops operating and a restitution factor (in this case a value of -6) takes over.
right now I'm trying to create a zero-sum situation where you have the same velocity coming out of the trampoline "bounce" (hero.y >= trampoline.y) as you did going in. That's just not the case as the traces reveal.
[Code]...
For now I'm hoping to have a solution where the velocity on the tic after the character leaves contact with the trampoline is the same (but negative) of the velocity just prior to going in. Heck I've even tried storing and retrieving the entry position and velocity, but that just looks like a hiccup.
I wanted to study some physics code lines related to flash actionscript 2.0.Is there anyway to build a model with physics incorporated without a physics engine? By bare actionscript?If yes, can anyone show me a tutorial or an explanation to learn somehting about it, please?
I know you can add a var to add grvity and velocity ect. But what are the limits of this?Can i have a ball roll downhill using physics from within flash, without a external physics engine like box 2D.Can i have impulses? Well thats not important just wondering really.What can you do with physics in flash?
Does anyone know the math to create this type of spectrum?
I'm using the F8 bitmap object and this image for a color preferences panel, and would like to use the same image for a fall-back to F7.
For F8, I'm using getPixel(), for F7 I'll need to determine the color (or as close an approximation as possible) using the math used to create this type spectrum.
I have XML data that looks like this: 197,168,198,168,204,168,206,168,207,169,208,etc This stuff is XY coordinate pairs, X1, Y1, X2, Y2, X3, Y3, etc. and are used by a drawing function to trace out a particular freeform shape. This array of data is usually 200-400 items long.Here is the AS code that is handling the reading of the XML and the drawing of the shape. This all works wonderfully:
[code]...
I am looking at the array and grabbing some points out, namely the first and last XY pairs, which I need for something else. That's the origXexp, origYexp stuff.The real problem is that I need to run a mathematical calculation on the data in this array. While this is a little hard to explain, I need to create a variable, let's call it expert_area, and then sequentially rip through that long string of numbers and do the following math (I'll use the simple X1 Y1 example): expert_area=0 expert_area = expert_area+((X1*Y2 - X2*Y1)/2)
where we move through the long string a pair at a time. So the first calculation would be (X1*Y2 - X2*Y1), the next would be (X2*Y3 - X3*Y2), (X3*Y4 - X4*Y3), etc. I've tried building loops to get the length of the expertArray[i] and then using that as the basis to proceed through the data. But everything I try either produces no results, or gets Flash stuck in an infinite loop. I'm unsure of where to put this, and how to construct it.
I'm trying to create a balance beam for an education video game and am having trouble making the balance look just right.When the student slides the weight on a triple beam balance, the beam rotates from its pivot to show how far off the weight is. The student then continues adjusting it until the weight matches. My problem occurs because the length of the weight arm means the rotation values are very small, range -4 to 4 degrees, and when the student gets within a few grams it appears level.
My question is how to create a mathematical curve. Like 100 = 20, 50 = 15, 20 = 10, 1 = 4, .2 = 2, etc, so that I can have large movements towards the more accurate side and less when the weight is far off.
I've gotten stuck on some issue using AS3 and RegEx. I'm trying to use a RegEx var to match out the ends of a mathematical expressions out of a string. But for some reason, the RegEx only matches the first expression and ignores the one after the conditional.
I'm completely useless at maths due to paying no attention whatsoever to it in school when I was a kid so forgive my lack of knowledge of basic terminology.I need a mathematical function that will return a number based on a graph that starts at 0, curves to (eg.) 100 and then curves back down to 0. I have a feeling it has something to do with Math.sin or somesuch wizardry but am not sure.Basically, I want to feed it a number between (eg.) 0 - 60 and for it to return a number on aforementioned curve. The purpose of this is to be applied as a lateral force on some basic ball physics. The idea of the 'curve' is that (depending on timing of the shot) there will be a 'sweetspot' in the timing.
I'm developing a project with Flex, Spring, Hibernate, MySQL, Tomcat, but one of the functionality is: " i have to store a mathematical rule like for example " a+b " into database, then in my human machine interface, i have two fields when user write the variables "a" and "b", then a button with the label calculate which if it's clicked, it'll show bellow the result of applying the rule " a+b " to the variables "a" and "b" which the user previously." Now, i'm searching for an Java or Flex API or any other way that will give me the ability to apply a mathematical rule stored in database as string, to variables i got from human machine interface"
I'm having a real problem trying to work this out...
A: I start with a movieclip on stage. it's 100x100.
B: I set xscale and yscale to 150.
C: I use "attachMovie" to add a little man into the square.The problem is, the man has an xscale of 100, but he is also scaled with the movieclip square container. So he appears too big.
D: What i would like to know, is what formula you would use to reduce his scale so he is the correct height, if the container movieclip had an xscale of 100?
I need to calculate the value of a formula which is passed dynamically by using text box.This formula contains a set of variables which are already declared and assigned a value(hard coded). I will provide a submit button , on clicking this button I must be able to evaluate the formula that I have passed dynamically using the text box.
I've been trying to look this up but not had any luck so far. I'm trying to make a simple pseudo-3D app, but I'm stuck on how to pull off the movement. If I have an object with x,y,z coordinates, and its movement speed, pitch, and yaw, what formula would I use for movement? So for example, if the object is at 0,0,0, moves 6 units per frame, and has pitch 30 degrees and yaw 15 degrees, what will be its coordinates next frame?
I am in need for some 2D physics seen from "above and straight down". Basicly I can sum it up with a "throwing balls into walls" kinda physics.
There seem to be quite a few physic engines for as3 out there, but I wonder if anyone have anyone special to recommend regarding my particular need as well as performance of the engines.
I'm trying to create a simple top game. Except, the movement of toy tops isn't so simple.I've been able to get the top to trace out squashed loocking spirals. However, the motion isn't random and there's no object detection. I was thinking that some variation of a bouncing ball script might work. However, the movement would have to be confined to the appearance of a perspective plane (so that it looks like it is spinning on something flat)
I have a little math problem with a game I'm making, and I can't for the life of me figure out the formula needed to accomplish something..Say, there's a sniping game, and a BIG image that must scroll from left to right according to the mouse movement.
Something like this:[URL]... In that example, the scene is 550 pixels wide, and the image is 1100, exactly two times the scene, so the formula is kinda easy..
[Code]...
the center of the image would be at x 1500, way over to the right of the scene, outside it, but it would fit inside the screen, like this (the blue square represents the real size of the scene):[URL]..Then when the mouse is at the far right side, that is 550 x, the image center should be at -950 x, like this:[URL]...
I'm not that good with Math and i have a formula for a that it's universal from what i understood but i dont know how to transform it to work with Flash's Math API.
I've been searching for the formula used intrinsically in Flash but I couldn't find anything. Does anybody know how the result colors are obtained when the 'layer' blend mode is chosen for the upper object? I thinks it's done separately in each channel using the transparency values.There might be some bitwise operations going on there but I'm not sure.
i'm trying to dynamically layout a calendar using actionscript and i'm no good at determining algorithms to quickly and efficiently lay things out.what i want to do is set it up per the image attached:
* where there are 7 columns and a varying number of rows.
* the top row has the 2 arrows and the month and year display.
* the second row has all the day headings, i.e. S, M, T, W, R, F, S
* and the rest of the rows will have the dates.
how do i come up with a nice clean formula to calculate the positions so all these elements align?
When I print out the loan_amount I get a 0.If I do: var loan_amount = (Math.pow(trm, (1 + apr)) -1); it will give me the result 1.0331079714165e55
As soon as I add the next part of the equation (apr / (Math.pow(trm, (1 + apr)) -1 )); it will give me the actual apr value as the result instead of the apr divided by the 1.0331079714165e55.Likewise, if I try to add a fixed value instead of the apr variable, it will return that fixed value instead of doing the math.
I want to make a game using physics in Flash, so I stumbled upon Box2D, but i find that hard to use [the basics are simple, but when i see the scripts,so i was wondering if there are easy to use flash physics engines?
There are some open SDK for Flash, that could be done. Rotating photos with physics? Examples of such programs BumTop, ePic, Coloris (no physics). The photo on the plane, it can be moved to the real physics?
I need help with one of my Flash projects,I'm trying to use gskinners shape based collision detection, but for some reason I cant get it to work, but im pretty new to using classes, so I dont understand the structure too much. Can i get a tutorial on how to use the gskinner class? im using the as2 version.heres the code, bare with me, there's a lot here. in all codes, mc1 is the track outline MC, and mc2 is the car
basicly im making a 2D top down version of WipEout HD Fury, so file structure is something like this (the .fla is called wipeout as3 because i was initialy coding in as3 and never changed the filename).wipeout as3.fla (the flash file containing all the MCs and animations, but only enough coding to import all of the external code files, as well as the VCam and its script) the code is;
Code: Select all #include RaceControl.as"
the RaceControl.as is used to determine the Car's control scheme, and refers to a physics code called RaceCar.as. i found it on the interwebs, all credit to matt carpenter;
Code: Select all// Race control
// Create key listener[code]........
the Bounce Function is my own work, and is what i want to happen when a collision is detected.now, the movieclip used for the car is my own drawn design, as is the track, and i want to use GSkinner's shape based collision to detect the collisions properly. so far i have the car driving around quite happily but i need it to collide with the walls of the track, rather than drive right through them.
I need to animate little blocks to fall down when rollovered... but i want them to start falling and keep falling once mouse hittests with it... so when the mouse isn't over the clip... it keeps falling... does anyone know how i can do this? and if anyone knows some good actionscript for elastic falling with slight rotation that would be sweet....
Iīd like to know how would I make a formula for the calculation of speed.Itīs not as simple as distance divided by time.I want something different.I have an helicopter.This helicopter is landed.He will take off with a small speed, but increasing speed.What I want is.This helicopter movement. In other words, increasing vertical speed, in a given time, say, 2.4 seconds, in a give distance, say, 100 pixels.After that he keeps vertical speed constantly. So I think the helicopter will start with its vertical speed slow, increasing, then, decreasing untill it reachs its constant vertical speed.
how to convert it to 0 and also if the number wsa 9, convert it to 1, and if it was 8 it gets converted to 2.. and so on.. where if it was 0 it would then be 10 Is there a formula? The 0 to 10, and 10 to 0 may not be possible but that's ok.
