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Resizing an image in an HTML5 canvas
...hem to speed it up, but I was having trouble figuring out how to make this into a multithreaded algorithm
– Telanor
Jul 11 '10 at 22:52
3
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Why are these constructs using pre and post-increment undefined behavior?
...n the semantics, instead of i.e. requiring that all implementations handle integer overflow in the exact same way, which would very likely impose serious performance costs, they just left the behavior undefined so that if you write code that causes integer overflow, anything can happen.
So, with th...
Why would iterating over a List be faster than indexing through it?
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In a linked list, each element has a pointer to the next element:
head -> item1 -> item2 -> item3 -> etc.
To access item3, you can see clearly that you need to walk from the head through every node until you reach item3, since you cannot jump direct...
To underscore or to not to underscore, that is the question
...PORTANT UPDATE (April 12, 2016):
It was brought to our attention that the internal standard of the .NET CoreFX team insists on using the underscore-notation without giving any insights as to why. However if we look closely at rule #3 it becomes evident that there is a system of _, t_, s_ prefixes t...
performSelector may cause a leak because its selector is unknown
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What's going on here is you're asking the controller for the C function pointer for the method corresponding to the controller. All NSObjects respond to methodForSelector:, but you can also use class_getMethodImplementation in the Objective-C runtime (useful if you only have a protocol reference, l...
Good example of livelock?
... = d; }
public synchronized void use() {
System.out.printf("%s has eaten!", owner.name);
}
}
static class Diner {
private String name;
private boolean isHungry;
public Diner(String n) { name = n; isHungry = true; }
public...
Objective-C ARC: strong vs retain and weak vs assign
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retain is the same as strong.
apple says if you write retain it will auto converted/work like strong only.
methods like "alloc" include an implicit "retain"
Example:
@property (nonatomic, retain) NSString *name;
@synthesize name;
4.assign
assign is the default and simply performs a variabl...
Fixed point vs Floating point number
I just can't understand fixed point and floating point numbers due to hard to read definitions about them all over Google. But none that I have read provide a simple enough explanation of what they really are. Can I get a plain definition with example?
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How to use enum values in f:selectItem(s)
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JSF has a builtin converter for enum, so this should do:
@ManagedBean
@ApplicationScoped
public class Data {
public Status[] getStatuses() {
return Status.values();
}
}
with
<h:selectOneMenu value="#{bean.question.stat...
The purpose of Model View Projection Matrix
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Because matrices are convenient. Matrices help to convert locations/directions with respect to different spaces (A space can be defined by 3 perpendicular axes and an origin).
Here is an example from a book specified by @legends2k in comments.
The residents of Cartesia ...