Actionscript 3 Dynamic line drawing with changing alpha - actionscript-3

I have been creating a training tool for a customer in Flash, using Actionscript 3. In it i have to create one continuous line generated over time, whose alpha is controlled by a static object and its distance from a continuous moving object. The closer the two are, the stronger the line, the further the weaker. This alpha only effects the the line at the current time, leaving the historical alpha as it was when the the line was produced. The way I have currently made it is by generating lots of small lines, which when joined together make one big line. Thus each small line has a different alpha. The overall effect is to create fade ins and outs based on the distance between the two objects with historical alpha still showing. Does anyone out there have a better way of achieving this effect? Hopefully, I have not just confused everybody.

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Locate/Extract Patches from an Image

I have an image(e.g. 60x60) with multiple items inside it. Items are in the shape of square boxes, with say 4x4 dimensions, and are randomly placed within the image. The boxes(items) themselves are created with random patterns, some random pixels switched on and others switched off. So, it could be the same box repeated twice(or more in case of more than 2 items) in the image or could be entirely different.
I'm looking to create a deep learning model that could take in the original image(60x60) and output all the patches in the image.
This is all I have for now, but I can definitely share more details as the discussion starts. I'd be interested to weigh in different options that can help me achieve this objective. Thanks.
I would solve this using object detection. First I would train a network to detect those box like objects by cutting out patches of those objects. Then I would run a Faster R-CNN or something like this on it.
You might want to take a look at the stanford lecture on detection (slides here: http://cs231n.stanford.edu/slides/2017/cs231n_2017_lecture11.pdf).

HTML5 Canvas not preserving the draw order

I am trying to draw a rough outline of a building in canvas.
I'm achieving the effect below by creating a series of squares for each side, plus the top 'roof' and then drawing them in sequence basically following the Painter's algorithm.
The screenshot on the left is showing how it should look. This is painting each square separately.
To improve performance I want as few .stroke() and .fill() calls as possible so I queue up all the moveTo() and lineTo() calls and paint them all in one big go.
Tests have shown that (at least for lines) this gives a massive performance improvement and I've verified it myself.
Unfortunately as you can see from the right screenshot, when I paint the buildings only once at the end the layering basically gets destroyed. It paints things in a seemingly random order.
Is the canvas supposed to work this way? Why doesn't it draw everything in the order I told it to draw in like the first screenshot?
Does anyone know a good work around for this behaviour?
If you're sending it all the moveTos and lineTos etc as one big batch, it's going to draw them as if you were rendering one large shape (where you'd want to see all the inner strokes).
There's a minor performance penalty for running multiple draw operations, but it's usually not worth making your code harder to understand and debug.

programmatically create Background Images in Flex 3

I'm developing a visualization for certain parts of a Warehouse with Flex 3. In this visualization there are lot of blocks where 1 to x pallets can be placed where x is between 9 and 15. I need to represent each pallet with a black square, each place which is already assigned to a pallet but not physically taken with a grey square and each free place with a white square. I first thought to just use a canvas for each place on a block and change their color if the state changes. But the hundreds of canvases which are there as a result of this approach are not updated quickly enough for my purposes (screen freezes for a few seconds).
I don't want to use embedded images because of the great amount of images I had to embed in the application (those Images appear in 4 orientations).
My idea was to create background images which reflect the state of the whole block only when needed for that certain state and cache them, so that the computation time is spread over the whole runtime.
My problem now is I don't know how to create them in a way that I can use them as "backgroundImages". As far as I understand I would need them as a class object but I don't know how to achieve that, when not embedding the images.
I'm of course open to better approaches to solve my problem. Thanks for your support.
I would suggest using Graphics property of a Sprite for example. It provides basic drawing API, like drawing lines, circles and rectangles.
Besides, you can draw bitmap images on the Graphics to produce more advances results.

Store a "routine" which, given some input, generates a 3d model

Well, it's the time of the year were I get busy on my next-generation, cutting edge, R&D project (just for the fun of it...and maybe some profit eventually).
This time, I've had a great idea for a service, which unfortunately I can't detail much.
However, a major part of this project is the ability to generate a 3d model out of certain input criteria. The generated model must be different on each generation.
As such, this is much different than the static models used in games - I think I will have to store actual code more than just model coords.
To give an example of some output:
var apple = new AppleGenerator();
apple->set_size_between(30, 50); // these two numbers are just samples...
apple->set_seeds_between(3, 8); // apple must have at least 3 seeds*
var apple_model = apple->generate();
// * I realize seeds may not be exactly part of the model, but I can't of anything else
So I need to tackle some points here:
How do I store these models as data?
Do you know of any tools that may help?
I need to incorporate a randomness factor (for example, the apples would have slightly different shapes each time)
I suppose math will play a good part here, but since these are complex shapes, it's going to be infeasible to cook up the necessary formulae for each model, right?
Also, textures must be relevant to each part of the model, as well as making the model look random (eg; I could be detailing a 40 to 60 percent red, and the rest green, for the generated apple).
This is in fact not a simple task. The solution varies a LOT depending on the complexity and variety of the objects you are trying to create.
Let's consider a few cases though:
Object is more or less known:
The most simple case is, to have a 3d model in the conventional way, and then randomize it a bit. Take the apple for example. The randomization can vary from the size of the apple to its texture colors to fruit damage.
All your objects can be described using NURBS surfaces:
In this case, you need to store enough data for the surface to be able to be generated, where of course this data can be randomized a bit.
Your objects have rotational symmetry:
In this case, generating a single curve and rotating it around the an axis can give you a shape. An apple is an example. You would need to store only the curve data and randomizing the shape could either be done on the curve (keeping symmetry) or on the final mesh.
On textures
This is way more complicated than the mesh generation. This is mainly because textures carry much more information than meshes (they are more detailed). You can have many texture generation strategies. In the case of your apple, you could select a few vertices, give them colors (one red, one green, another red etc) and interpolate the other vertex colors. This creates a smooth transition of colors which may look nice on an apple. If you are generating a knife however that just looks terrible.
In most cases, you need to be aware of which part of your mesh represents what, and generate the texture part by part. In the knife example above, you can generate the mesh in two steps; blade and handle each part's texture generated separately.
Conclusion
You can have a mixture of these of course. A meshGenerator class can take the data and based on whichever type they are, generates a mesh accordingly. Perhaps the first solution for object creation is the most suitable as any complicated object can be more easily defined by its triangles rather than NURBS.
Take a look at some of the basic architectural principles used to code Spore, the video game about evolving living creatures: http://chrishecker.com/My_liner_notes_for_spore
Here's an example of how to XML-serialize a mesh, along with some random morph behavior: http://www.ogre3d.org/tikiwiki/Morph+animation#The_XML_format_of_meshes_with_morph_animation
To make your apples all a bit different, you can apply a random transformation (or deformation). See for example: http://wiki.blender.org/index.php/Doc:2.4/Manual/Modifiers/Deform/MeshDeform
You want to use an established file format to avoid strange problems. It's more geometry than pure math. Your generate function would plot the polygons, and then your save method would interact with the formats.
https://stackoverflow.com/questions/441388/most-common-3d-model-format

Randomly Generate Directed Graph on a grid

I am trying to randomly generate a directed graph for the purpose of making a puzzle game similar to the ice sliding puzzles from pokemon.
This is essentially what I want to be able to randomly generate: http://bulbanews.bulbagarden.net/wiki/Crunching_the_numbers:_Graph_theory
I need to be able to limit the size of the graph in an x and y dimension. In the example in the link, it would be restricted to an 8x4 grid.
The problem I am running in to is not randomly generating the graph, but randomly generating a graph which I can properly map out in a 2d space, since I need something (like a rock) on the opposite side of a node, to make it visually make sense when you stop sliding. The problem with this is sometimes the rock ends up in the path between two other nodes or possibly on another node itself, which causes the entire graph to become broken.
After discussing the problem with a few people I know, we came to a couple of conclusions that may lead to a solution. Including the obstacles in the grid as part of the graph when constructing it. Start out with a fully filled grid and just draw a random path and delete out blocks that will make that path work, though the problem then becomes figuring out which ones to delete so that you don't accidentally introduce an additional, shorter path. We were also thinking a dynamic programming algorithm may be beneficial, though none of us are too skilled with creating dynamic programming algorithms from nothing. Any ideas or references about what this problem is officially called (if it's an official graph problem) would be most helpful.
I wouldn't look at it as a graph problem, since as you say the representation is incomplete. To generate a puzzle I would work directly on a grid, and work backwards; first fix the destination spot, then place rocks in some way to reach it from one or more spots, and iteratively add stones to reach those other spots, with the constraint that you never add a stone which breaks all the paths to the destination.
You might want to generate a planar graph, which means that the edges of the graph will not overlap each other in a two dimensional space. Another definition of planar graphs ist that each planar graph does not have any subgraphs of the type K_3,3 (complete bi-partite with six nodes) or K_5 (complete graph with five nodes).
There's a paper on the fast generation of planar graphs.