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I've made my first steps in Adobe Illustrator, and I like it very much..
I'm an expert in Photoshop so many things seemed familiar to me.
There's one thing, I haven't been able to find an answer for on the net..
Maybe anybody knows this?
Layers and sublayers appear with a grey background in the layer window.
Groups appear with a white background in the layer window.
But they both seem to have an identical behaviour.
Is there any difference between a 'layer/sublayer' and a 'group'?
Why does Illustrator distinguish them?
I'm using Illustrator CS2.
Thanks for your help!
I really appreciate it.
Greetings
Christopher
Technically, there is very little difference. Internally, in the Illustrator artwork tree, both layers and groups perform the same function - they create a parent object that can contain one or more child objects. The differences lie in how they are used in a practical sense.
Groups are typically used to bundle artwork that you want to stay together when moving or scaling. For example, let's say you draw a door. It might contain inset panels and a door knob. When you want to move it, you can direct select each object or marquee select all the objects before moving, but that is slow and can also pick up additional art objects that may be in the way. Alternatively, if you group the door outline, the inset panels and the door knob, now all you need to do is click once on any of those objects to select the entire door.
Layers are typically used to manage visibility and stacking order. For example, let's say you draw a floor plan for a home. On one layer you might draw the walls. Then, on other layers you might draw electrical plans, furniture layouts, and plumbing plans. When you contract with an electrician, he may not need to see the furniture layout, so you would set the visibility of the furniture layer to false so that the printout would not contain any furniture. Also, you need to ensure that furniture is always drawn over walls, so you would use the layer panel to move all furniture at once above the walls layer.
Incidentally, an easy way to select everything in a layer (and thus make them act even more like a group and muddy the waters of how these two things differ even more!) is to click on the small circle icon on the right of the layers panel. This selects everything, including groups, within that layer. Additionally, holding down alt and then clicking selects everything in all the layers.
A highly useful aspect of using layers is the ability to lock and hide elements while you're working. These are found on the left hand side of the layers panel. It should be clarified that you need to keep your drawing in good order as you go along to maximise the usefulness of this feature.
It is also worth mentioning that groups cannot be made up of elements from different layers. Attempting to do so will move everything to the currently selected layer and grouping it there.
The main use for groups I have found is for ease of selection if I have certain elements within a layer that will use the same appearance settings as each other, but that are different to the rest of the layer. Doing so allows me to simply click once to select the whole group and then apply the desired appearance settings.
Ultimately, how you use layers and groups is entirely a case of personal preference and what makes sense to you as to how to use the strengths of each e.g. as mentioned in the previous answer, grouping allows the same scale factor be applied to each element within, and also prevents them from losing their positions relative to each other if you use the arrange / align buttons on the top menu bar. Personally, I tend to use layers to break down what each type of element is representing; for instance I had to make a fair few maps studying architecture, so I would have a layer named contours, buildings etc. which would broadly use the same appearance so I could alter these quickly if I needed to by using the select method I mentioned above. Occasionally there would be groups within these layers, which admittedly I could have placed in additional layers instead.
Really, if it makes sense to you then run with it.
Related
I need help designing a game where characters
have universal actions(sit, jump, etc.) or same across all characters; roughly 50 animations
unique attack patterns(different attacks) roughly 6 animations per character
item usage attacks(same across all characters) roughly 4 animations per item which could scale to 500+
What would be the best way to design this? I use blender for animations. And I just started a week ago.
I’m thinking of using either one model for everything and limiting actions or to create multiple and import those separately. Any help is appreciated!
Edit: also considering optimization since I don’t want lag to incur; making a mmo like game.
There is an initial release (MIT License) of the module GodotAnimationRetargeting that I referenced in comments. Update: There is a GDScript version now.
Usually in Godot you have an animation player with the animations tied to a given model. Which means you would have to add them for all the models. However, this module allows you apply animations from an animation player to another model. You can also apply them partially (e.g. only rotation, or position or scaling of bones).
That should help you have a common set of animation applied to different models.
Being a module it requires to compile Godot using it. See Compiling on the Godot docs.
In 2007, when I was young and foolish and before I knew about Open Street Map, I started an urban historical map project. I was working in Illustrator, it was going to be an interactive Flash piece, and my process was to draw the maps first, with the thought that I'd label some, but not all, of the street later on.
As we know Flash was began to die about 2010 and I put the project away for a number of years. I picked it up again a couple years ago and continued my earlier practice of just drawing streets and water features, this time with the intention of making it a conventional web map. Now I'm pretty close to finishing the drawing of a five-layer (1871, 1903, 1932, 1952 and 2016) historical map of a medium-sized city, though it still lacks labels.
My problem now is how to add large numbers of labels, many of them duplicates. There could be as many as 10,000 for all five layers, though as a practical matter I may have to settle for a smallish fraction of that number. Based on web searches I gather my workflow is unusual and that mine is therefore an unusual problem.
I've exported my maps and brought them into QGIS and played with the software a little. The process of adding labels to objects doesn't seem terribly efficient or user-friendly, but that's probably due to my unfamiliarity with the program.
So my question is this: Are there any tricks to speed up the painful process of adding large numbers of duplicate labels in either QGIS or ArcGIS? Since so many of the streets exist in all five layers, functionality like the ability to select multiple objects in different layers and edit their attributes simultaneously in the Attribute Table would be a godsend. (Doesn't seem possible.) So would the ability to copy the attributes from one object and paste them onto other objects. Or the ability to do either of these things in Illustrator via a plugin and then export the data along with the shapes to a GIS program.
Thanks for your help!
If I understand the issue correctly I think are several different solutions. When you say that you
Typically for a spatial layer in ArcGIS or QGIS you define how to label all features in a layer once by defining a label scheme to use across all features, 1 or 1 million. This assumes that each feature in the layer has one or more attributes in the associated table for the layer.
How are you converting the Illustrator vectors to a spatial layer? DXF?
You will likely have better/faster responses to this question by posting it to the GIS Stack exchange. https://gis.stackexchange.com/
I mean, the basics..
1) I have seen in the Online videos, that they are modelling a character (or anything) through one object only, they are extruding, loop cut, scaling, etc and model a character, why don't they design different objects separately (like hands separately, legs separately, body separate and then join them together and make one object)..??????
2) Like What the texturing department has to see so that they should not return the model back to the modelling department. I mean like the meshes(polygons) over the model face must be quad, etc not triangle. while modelling a character..
what type of basics i should know , means is there any check list or is there any basics which i should see before modelling a character..
Please correct me if i am wrong , and answer my both questions.. Thanks
It may be common but it definitely isn't mandatory to have a model as one solid mesh. Some models will have parts of the body underneath clothing removed to reduce the poly count. How the model is to be used will be a big factor to how you model it, that is a for a single image it is easy to get away with multiple parts, while a character that will be animated in a cartoony animation could be stretched and distorted in ways that could show holes in a model with multiple pieces. When working in a team, there may be rules in place determining whether a solid or multi-part model is considered acceptable.
An example of an animated model made from multiple parts is Sintel, the main character in the Sintel short animation.
There is nothing stopping you from making a library of separate body parts and joining them together when you make your model. Be aware that this can bring complications, if you model an arm with 12 verts and then you make your hand with 15, then you have to fiddle around to merge them together.
You will also find some extra freedom to work with multiple body parts during the sculpting phase as you are creating a high density mesh that is used as a template to model a clean mesh over. This step is called retopology.
It is more likely that the rigging department will send a model back for fixing than the texturing department. When adding a rig and deforming the mesh in different ways, any parts that deform badly will be revealed and need fixing.
[...] (like hands separately, legs separately, body separate and then
join them together and make one object) [...]
Some modelers I know do precisely this and they do it in a way where they block in the design using broad primitive shapes, start slicing some edge loops and add broad details, then merge everything together, then sculpt it a bit further with high-res sculpting tools, and finally retopologize everything.
The main modelers I know who do this, however, model in a way that tries to adhere as close as possible to the concept artist's illustration. They're not creating their own models from scratch but are instead given top/front/back/side illustrations of a character, for example, and are just trying to match it as closely as possible.
When you start modeling everything in small pieces, it helps to have that concept illustration since you can get lost in the topology otherwise and fusing organic meshes together can be difficult to do in a clean way.
[...] why don't they design different objects separately? [...]
Again they sometimes do, but one of the appeals of creating organic meshes by keeping it seamless the entire time is that you can start to focus on how edge loops propagate across the entire model. It helps to know that the base of a finger is a hexagon, for example, in figuring out how to cleanly propagate and terminate the edge loops for a hand, and likewise have a strategy for the hand to cleanly propagate and terminate edge loops as it joins into the forearm.
It can be hard to get the topology to match up cleanly if you designed everything in small pieces and then had to figure out how to merge it all together. Polygonal modeling is very topology-oriented. It tends to require as much thinking about the wireframe and edge flows as it does the shape of the model, since it needs to be a certain way for everything to subdivide cleanly and smoothly and animate predictably with subdivision surfaces.
I used to work with developers who took one glance at the topology-dominated workflow of polygonal modeling and immediately wanted to jump to seeking alternatives, like voxel sculpting. With voxels you could be able to potentially model everything in pieces and foose it all together in a nice and smooth organic way without thinking about topology whatsoever.
However, that loses sight of the key appeal of polygonal meshes. Their wire flow forms a control lattice with a very finite number of control points for the artist to animate and move around to predictably control the shape of their model. You immediately lose that with a voxel representation -- so while voxels free the artist of thinking about how the topology works and how the wireframe flows through the model, it also loses all those control benefits of having that. So often if people use voxel sculpting, they end up meticulously retopologizing everything at the end anyway to gain back that level of coarse and predictable control they have with polygonal meshes.
I mean like the
meshes(polygons) over the model face must be quad, etc not triangle.
while modelling a character..
This is all in the context of subdivision surfaces: the most popular of which are variants of catmull-clark. That favors quads to get the most predictable subdivision. It's much easier for the artist to predict how everything will look like and deform if they favor, as much as possible, uniform grids of quadrangles wrapped around their model with 4-valence vertices and every polygon having 4 points. Then only in the case where they kind of need to "join" these quad grids together, they might create some funky topology: a 5-valence vertex here, a 3-valence vertex there, a 5-sided polygon here, a triangle there -- but those cases tend to deform a bit unpredictably (at least unintuitively), so artists tend to try to avoid these as much as possible.
Because when artists model polygonal meshes in this way, they are not just trying to create a statue with a nice shape. If that's all they wanted to do, they'd save themselves a lot of grief avoiding dealing with things in terms of individual vertices/edges/polygons in the first place and using something like Sculptris. Instead they are designing not only shapes but also designing a control lattice, a wire flow and a set of control points they can easily move around in the future to get predictable behavior out of their control cage. They're basically designing controls or an "interactive GUI/rig" almost for themselves with how they design the topology.
2) Like What the texturing department has to see so that they should
not return the model back to the modelling department.
Generally how a mesh is modeled in a direct sense shouldn't affect the texture department's work much at all if they're working with UV maps and painting textures over them (at that point it doesn't really matter if a model has clean wire flows or not, since all the texture artists do is pain images over the 2D UV map or directly onto the 3D model).
However, if the modeler does the UV mapping, then regardless of whether he uses quad meshes and clean wire flows or not, if the UV mapping is poor, then the resulting texture images will look all distorted. So the UV maps need to be made well with minimal distortion, though that's usually easy to do automatically these days.
The other exception is if the department doesn't use UV maps and instead uses, say, PTex from Disney. PTex really favors quads. In the original paper at least, it only worked with quads.
How can i detect if two or more objects collide?
I would like to use only default frameworks, such Core Graphics. Or i have to use Box2d or Cocos2d?
EDIT
You're right, the question isn't really clear.
So this is the situation :
i have multiple UIImageView which move with the accelerometer, but i want that when two or more images collides these isn't overlap each others. Is it clear?
Probably you want a multi-step process.
First, define a "center" and "radius" for each object, such that a line drawn around the center at the selected radius will entirely encompass the object without "too much extra". (You define how hard you work to define center and radius to prevent "too much".)
An optional next step is to divide the screen into quadrants/sections somehow, and compute which objects (based on their centers and radii) lie entirely within one quadrant, which straddle a quadrant boundary, which straddle 4 quadrants, etc. This allows you to subset the next step and only consider object pairs that are in the same quadrant or where one of the two is a straddler of one sort or another.
Then, between every pair of objects, calculate the center-to-center distance using the Pythagorean theorem. If that distance is less than the sum of the two objects' radii then you have a potential collision.
Finally, you have to get down and dirty with calculating actual collisions. There are several different approaches, depending on the shape of your objects. Obviously, circles are covered by the prior step, squares/rectangles (aligned to the X/Y axes) can be computed fairly well, but odd shapes are harder. One scheme is to, on a pair of "blank" canvases, draw the two objects, then AND together the two, pixel by pixel, to see if you come up with a 1 anywhere. There are several variations of this scheme.
As mentioned, your question is pretty vague, and therefore difficult to answer succinctly. But to give you some ideas to go by, you can do this with core animation, though some 3rd party gaming engines/frameworks may be more efficient.
Essentially, you create a timer that fires quite often (how often would depend on the size of the objects you're colliding and their speed - too slow and the objects can collide and pass each other before the timer fires - math is your friend here).
Every time the timer fires you check each object on screen for collisions with the others. For efficiencies sake you should ensure that you only check each pair once - ie. if you have A,B,C,D objects, check A & D but not D & A.
If you have a collision handle it however you want (animation/points/notification/whatever you want to do).
There's way too much to cover here in a post. I'd suggest checking out the excellent writeup on the Asteroids game at cocoawithlove, especially part 3 (though not iOS the principles are the same):
http://cocoawithlove.com/2009/03/asteroids-style-game-in-coreanimation.html
There are lots of non-image-based CAPTCHA ideas floating around. But what about the old-fashioned way?
What are the elements of a good image CAPTCHA? What visual elements are hard for computers, but easier for humans? What about mistakes, elements that are easier for computers than they are for humans? What are good techniques for increasing the speed of a CAPTCHA generator?
Here's an example of a CAPCHA I've been working on. It generates the functions for two sine waves, then stretches a text between them. It lays that over a background drawn from a pool of images.
How could this be improved? (Specifically, I'm using PHP GD.) Things that come to mind are:
Change the color of the text, possibly making it multicolored.
Add "scratches" or marks that mildly obscure the text.
Add to the distortion so that it's affected by sine waves horizontally as well.
What goes into a superb image CAPTCHA?
Edit:
I know that there are some very worthy third-party CAPTCHA resources. I'm looking for attributes that make them good. I'd like to use my own CAPTCHAs, just for the purpose of self-improvement. So, you can talk about reCAPTCHA, but it's not exactly what I'm looking for.
Also, it has been brought up that not only the image, but also the experience matters, so feel free to comment on that.
Make each letter/number out of a pattern, I.E. unconnected dots. Meaning the computer has no way of knowing that a dot is part of a letter other than pattern recognition (which they don't have yet.) Then the usual distortions and random lines.
How you do this is the challenge.
EDIT: Also, bonus points for patterns of different shapes, and try alpha transparency on the characters (on the edges or the whole character), so they merge with the background.
Make letters difficult to separate. Use handwriting-like font or add lines that join letters. Decrease and randomize spacing between letters.
Add wave distortion in other axis too. Distortion in one axis only can be relatively easily analyzed and reversed.
Don't bother with color background at all. It's super-easy to automatically filter black from other colors. Your background hinders only humans.
Don't add scratches or other noise unless it has the same thickness as letters. Noise-removal algorithms can easily remove things that are thinner than letters.
What if the color of the letters faded into other colors... for instance the 5 can start off as yellow on top and fade into blue or something. The colors chosen should be random.
With the multicolored background it might make it hard for the computer to pickup where the background ends and the character begins.. and hopefully it would not be too difficult for the human to actually pick up the pattern.
Instead of generating captcha you can create a captcha table in your database and you yourself create the table by search on google for good captcha images.
So no need to worry "Will this generation method work?"
I really hate CAPTCHA on sites, they just annoy me, but if you want to try and make a robust one try the following:
Ability to get a new image without submitting
Spoken version for the visually impaired
Non-uniform characters
I've used Recaptcha on a few sites, it's a nice and robust solution.
Or if you want to be really funky about it check out this: http://research.microsoft.com/asirra/
Algorithms that try to break captcha are pattern matchers that work by a few different ways: scaling and skewing the symbols that they already know about, finding and tracing edges, and counting interior holes to help. If you can break the letter up into pieces, vary the letter quality, or add strong lines or “scratches” along the letters these techniques will help. However all of this is fairly moot considering we have recaptcha for this purpose and it’s a wonderful third party app for this. Additionally captcha will help the security of your site, but will not stop those who are truly enticed.
I like the idea of KittenAuth and Microsoft's Asirra project. The idea is that, while OCR will eventually evolve to break your traditional captcha, the ability to distinguish a kitten from a dog is many orders of magnitude more complex a problem, while absolutely trivial for humans.
This solution, while probably the sexiest captcha idea ever, has the limitation of not being easily portable to hearing-impaired methods.
What about shearing and shuffling bands to mangle display and mouse-only input?
Start by taking your sine-wave morphed text, divide into horizontal bands or maybe even a grid.
That makes optical recognition harder and might allow you to avoid the kind of nasty background games that make some captchas hard for humans.
For a site where you can rely on local drag in the browser, instead of typing in an entry use shuffling requiring the user to re-order pieces (just in sloppy order, not like one of those puzzles). Or, if you wanted to use clicks alone, the classic sliding tile puzzle.
Note, I've run into a captcha where you had to identify which of N cartoons had an animal in them which succeeded in blocking me!
Wellington Grey sums up the AI CAPTCHA race nicely.
You could add a random array of fonts so that GD renders each character using a different one.
Be wary of suggestions of ReCaptcha. I have submitted incorrect input into it a couple few dozen times, and have had success each time. Several of those times I have submitted incorrect input for both words rather than just the most obscured word; the success rate, as I said, has been 100%.
I also think that image-based CAPTCHAs are user-hostile and should be avoided wherever possible. The advantage of text-based solutions is that you can tailor them to your site's audience, adding a level of obscurity that may trip up machines as they become more savvy with text-based solutions.
At the very least, don't use this all the time:
(source: codinghorror.com)