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Hi, hope somebody can help me or at least give a comment.
I'm working on a viewer for large image but the memory become the limit to view the whole image.
An idea from other gigapixel viewer is to seperate the whole image into small tiles(256x256) for a number of zoom level, create DC in memory and dynamically display(OnPaint) only viewable part.
But I'm having difficulty implementing this algorithm like how will i change DC in memory while scrolling and I can't find an open source showing such.
Does anybody have an idea how to implement this?
Please explain logic in more details like when scrollbar moved, mouse scroll or OnPaint().
Or if you knew of a thread or open source implementing like this please let me know.
That's all thank you.
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First, thank you for your time Rajkumar.
I have already seen that code and that is not the solution to my problem.
The bitmap the programmer referred as large was actually large enough for the display area or client rectangle but still can be loaded.
I actually mean "large image" that can't be loaded and will cause a memory error like a gigabyte size *.jpg image. The only way to load it is to tiled it into smaller size and manipulate like what HDView from microsoft or google map doing.
I just don't know how to implement it. I can't find detailed explaination regarding this matter.
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Maybe CXImage article is helpful for you I guess you need to read image files your self instead use of functions like LoadImgae,CImage ,....(you can find this article on the codeproject).
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Hi Mark,
Thanks Mark, I'll try that tomorrow.
Regards,![Rose | [Rose]](https://www.codeproject.com/script/Forums/Images/rose.gif)
Bram van Kampen
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Bram van Kampen wrote: ...I create a number of Folders. Is there a way of ensuring that the Created folders are available Shared for read and write over the Network.
After you create the folder, change its permission(s) by creating an ACE. Then add that ACE to the ACL.
"Normal is getting dressed in clothes that you buy for work and driving through traffic in a car that you are still paying for, in order to get to the job you need to pay for the clothes and the car and the house you leave vacant all day so you can afford to live in it." - Ellen Goodman
"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne
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i have a form having five different textboxes in vc++,
and i need to copy all integer values from this textboxes to a 2d array.
how can i do this.
please help.
thanks.
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CWnd::GetWindowText() / WM_GETTEXT to get the text from the control
Some version of strtol() to convert a string to an integer
The assignment operator (=) to assign the integer to the array.
Mark
Mark Salsbery
Microsoft MVP - Visual C++
![Java | [Coffee]](https://www.codeproject.com/script/Forums/Images/coffee.gif)
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sorry it isnt not clear enough.
can you give me more getails.
thanks
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Which part? Getting text from controls? Converting text to integer?
Copying an integer to an integer array? Are you using MFC or straight
Win32 APIs?
Mark
Mark Salsbery
Microsoft MVP - Visual C++
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i know how i can convert to integer. i use "Convert::Toint32" and i alsoo know how i can copy an integer to an array.
iwould like to know getting text from controls.
i am trying to create windows form application
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Ohhh it's a managed c++ app. You're in the wrong forum to start with.
The TextBox class has a property called Text. If you have a TextBox object
for the edit control, you can get its text with this property:
System::Windows::Forms::TextBox ^MyTextBox = ...;
...
int MyInt = Convert<font color="Red">::</font>ToInt32(MyTextBox->Text); Mark
*edit* fixed wrong operator
Last modified: 11mins after originally posted --
Mark Salsbery
Microsoft MVP - Visual C++
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What do you mean by "textbox"?
Is it a static control, edit control, listbox control?
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Hi,
I have made a small windows form application with a tableadapter. This is linked with an mdb file. Did this with the new dataset option.
Now I'd like to use the app.config file to make this connectionstring adjustable for placing the mdb file at another location. However program always looks to the connectionstring made with the wizard of the new dataset 
Can anyone help me solve this problem? Thanks
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I am trying to cut 3 bytes from the data read from the file and keep getting error. Here is the error and the code.
Error...
**************************************************
///error C2228: left of '.substr' must have
class/struct/union
***************************************************
Code...
#include "stdafx.h"
#include <iostream>
#include <iomanip>
#include <conio.h>
#include <string>
#include <fstream>
using namespace std;
string DataCut;
struct s {
char test[4];
char test1[4];
};
struct s myStr;
int _tmain(int argc, _TCHAR* argv[])
{
char *str1, Mycut[4];
char str[80000];
string sear1;
size_t result;
fstream file_op("c:\\ProjectRead.txt",ios::in);
while(!file_op.eof())
{
file_op.getline(str, 80000);
str1 = str;
*********************************************************************
Mycut = str.substr(0,4); /// Error here
cout << str1;
*********************************************************************
} file_op.close();
system("PAUSE");
return 0;
}
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I'm going to assume you mean compiler error.
You can't assign a basic_string<CharType, Traits, Allocator> to a char[4] array.
You could copy the basic_string to a char array...
strcpy(Mycut, str.substr(0,4).c_str()); or use an appropriate type
basic_string <char> Mycut = str.substr(0,4);
Mark
Mark Salsbery
Microsoft MVP - Visual C++
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Mark,
I use both code and did not help. I even create a struct like this
struct name {
char test[4];
char test1[4];
{
struct name myname;
strcpy(myname.test, str.substr(0,3);
I am still getting the same error.
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msogun wrote: strcpy(myname.test, str.substr(0,3);
I am still getting the same error.
Not surprised, since you are missing a right parenthesis. Even then, your compiler will complain about substr() not belonging to char.
"Normal is getting dressed in clothes that you buy for work and driving through traffic in a car that you are still paying for, in order to get to the job you need to pay for the clothes and the car and the house you leave vacant all day so you can afford to live in it." - Ellen Goodman
"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne
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I don't know why, but I assumed your str was a string object 
I recommend picking a string type and sticking to it - the mix of char arrays and
string classes just adds unnecessary confusion and complexity.
I'm pretty sure the error messages you are getting will tell you what's wrong.
Mark
Mark Salsbery
Microsoft MVP - Visual C++
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Also, if you're going to copy 4 characters to your Mycut array, you need to make
its dimension 5 to have room for the null terminator.
char Mycut[5];
Mark
Mark Salsbery
Microsoft MVP - Visual C++
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