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stringstream, string, and char* conversion confusion
... any changes to it might cause it to re-allocate and thus render cstr invalid. It is therefor safer to not to store the result of the call to str() at all and use cstr only until the end of the full expression:
use_c_str( stringstream.str().c_str() );
Of course, the latter might not be easy and c...
Exporting functions from a DLL with dllexport
... the internals of your lib but export some functions unmangled for use outside C++, see the second section below.
Exporting/Importing DLL Libs in VC++
What you really want to do is define a conditional macro in a header that will be included in all of the source files in your DLL project:
#ifdef LIB...
Generating an MD5 checksum of a file
...y warnings, that is perfectly good use of MD5.
– President James K. Polk
Aug 7 '10 at 20:09
22
@G...
what exactly is device pixel ratio?
...any different device pixel ratios, you should use CSS Media Queries to provide different sets of resources for different groups of devices. Combine this with nice tricks like background-size: cover or explicitly set the background-size to percentage values.
Example
#element { background-image: url...
Pass a data.frame column name to a function
...,"x","y")
x y z
1 1 5 6
2 2 6 8
3 3 7 10
4 4 8 12
This is often considered "best practice" since it is the method that is hardest to screw up. Passing the column names as strings is about as unambiguous as you can get.
The following two options are more advanced. Many popular packages make u...
What use is find_package() if you need to specify CMAKE_MODULE_PATH anyway?
...file.
Config mode (install)
<package>Config.cmake file located outside and produced by install
command of other project (Foo for example).
foo library:
> cat CMakeLists.txt
cmake_minimum_required(VERSION 2.8)
project(Foo)
add_library(foo Foo.hpp Foo.cpp)
install(FILES Foo.hpp DESTINAT...
What are Vertex Array Objects?
... A good description is found here.
Macros just remember the actions you did, such as activate this attribute, bind that buffer, etc. When you call glBindVertexArray( yourVAOId ), it simply replays those attribute pointer bindings and buffer bindings.
So your next call to draw uses whatever was b...
Using HTML5/Canvas/JavaScript to take in-browser screenshots
... have been working on a script which converts HTML into a canvas image. Decided today to make an implementation of it into sending feedbacks like you described.
The script allows you to create feedback forms which include a screenshot, created on the client's browser, along with the form. The scree...
How to determine if a number is a prime with regex?
...
You said you understand this part, but just to emphasize, the String generated has a length equal to the number supplied. So the string has three characters if and only if n == 3.
.?
The first part of the regex says, "any charac...
Proper practice for subclassing UIView?
...er, it's fairly simple to use the loadView and related viewWill , viewDid methods, but when subclassing a UIView, the closest methosds I have are `awakeFromNib , drawRect , and layoutSubviews . (I'm thinking in terms of setup and teardown callbacks.) In my case, I'm setting up my frame and i...