I use Dev-C++ , and I have a program in C where the output is not fully shown (only the last part is visible).
So, I tried with a simple program and I noticed the same problem , for example here :
#include <stdio.h>
#include <stdlib.h>
main(){
int i;
for(i=0;i<5000;i++){
printf("\n The number is : %d\n",i);
}
}
Well, when the program is finished, I only see in the Console numbers from (4852 to 4999), but I want to see all the output.
In most terminals you can scroll backwards to see what was printed earlier. In Windows, you can modify the visible history length by right-clicking on the titlebar at the top, choosing preferences and setting the Scrollback to as long as you like. In Linux, it is a property of the terminal emulator (try Shift-Page Up to scroll backwards).
You will need a 5000-line monitor. Try getting an array of the most powerful graphics cards you can buy and a high-res display array. Set the font to the smallest possible.
Alternatively, redirect the output to a printer and paste the output sheets to your wall.
Having the same problem I usually redirect the output to a text file.
Related
I can succesfully save video which I captured from c++ opencv there is no problem.
Bu similar code not capturing the video. Just opening out.avi . and only 6 kb.
I put the code in showframe func. there is no resizing fyi.
Anybody has experience with the opencv videowriter on the Qt?
void Widget::show_frame(Mat &image)
{
Mat resized_image = image.clone();
video.write(image);
int width_of_label = ui->label_camera->width();
int height_of_label = ui->label_camera->height();
Size size(width_of_label, height_of_label);
// cv::resize(image, resized_image, size);
cvtColor(image,image,CV_BGR2RGB);
cvtColor(resized_image, resized_image, CV_BGR2RGB);
ps : Platform MacOSX
I encountered the same problem with you, and I have tried many solutions, I think you can make the fifth parameter of videowriter（) be false. That is, VideoWriter out = VideoWriter(video_name, CV_FOURCC('D', 'I', 'V', 'X'),frame_fps,Size(frame_width,frame_height),false). This works for me！
make sure that your application has access to the opencv_ffmpeg*.dll. For example place it in the working directory or the PATH variable.
Try different codecs, too. Afaik, MJPG did work on all tested machines/systems so far.
I've already solved this by not displaying the last letter of the word then locating the last letter and making it blink then I displayed the word inversely minus the last letter of course.
#include<string.h>
#include<conio.h>
#include<iostream.h>
#include<stdio.h>
char text[255];
int txtposition,txtlength;
void main()
{
clrscr();
gets(text);
txtlength=strlen(text);
char lastchar=text[txtlength-1];
cout<<"Your text is: ";
for(txtposition=0;txtposition<txtlength-1;txtposition++)
{
cout<<text[txtposition];
}
textcolor(WHITE+128);
cprintf("%c", lastchar);
for(txtposition=txtlength-2;txtposition>=0;txtposition--)
{
cout<<text[txtposition];
}
getch();
}
Thank you for all your help!
To make the middle character blink, either your output terminal needs to be capable to present blinking characters using a special terminal control code as described here, or use the gotoxy() function from a separate thread, that displays a ' ' or the actual character, alternating for a specific blink frequency.
The standard C++ library does not provide any facility for making characters blink.
You can do that in platform-specific ways, but it's worth noting that Windows console windows do not (as far as I know) directly support text blinking, like the original IBM PC's text screen mode did. On the original IBM PC one bit of the color specification could be configured to either yield high intensity or blinking, with blinking control as the default. I always reconfigured it to high intensity in my programs, and in the corresponding mechanism for Windows console windows the bits always determine color.
So, it would be complicated to do even in Windows, unless you're running in a DOSBox, which emulates the old PC. I don't know what functionality it offers. Maybe it even does blinking.
But you can easily mark the relevant letters in other ways.
For example, you could use
uppercase versus lowercase,
underlining characters placed on the next line,
parentheses (as you did in your example here),
colors (platform specific),
a different font, boldness, whatever.
I recommend updating to a modern compiler, if you have an ordinary modern PC. Compilers are free. Also you need better learning material, e.g. void main is non-standard and is only accepted by a few compilers.
Looks like for Turbo C/C++ you can you use the Graphics library and/or builtin conio functions. ( https://answers.yahoo.com/question/index?qid=20080813072809AAEguz0 )
But the above is not portable as the graphics library is specific to Turbo and conio is specific to some dos based compilers/libraries.
If you move to the a complier like gcc/g++ then you might want to look at curses library: http://tldp.org/HOWTO/NCURSES-Programming-HOWTO/
I've got a really simple application for adding watermarks to pictures. So you can drop your pictures in a QListWidget which shows you a thumbnail and the path, adjust some things like the text, the transparency, the output format and so on.. and after pressing start it saves the copyrighted picture in a destination of your choice. This works with a QPainter which paints the logo and text on the picture.
Everything is able to work fine. But here's the misterious bug:
The application kills random letters. It's really strange, because I can't reproduce it. With every execution and combination of options it's different. For example:
Sometimes I can't write some letters in the QLineEdit of my interface (like E, 4 and 0 doesnt exist, or he changes the letters so some special signs).
The text of the items in the QListWidget aren't completly displayed, sometimes completley missing. But I can extract the text normally and use the path.
While execution I have a QTextBrowser as a log to display some interesting things like the font size. Although, the font is shown normaly on the resulting picture, it says " 4" or "6" instead of much higher and correct sizes. Betimes strange white blocks appear between some letters
When drawing text on the picture with a QPainter, there also letters missing. Sometimes, all the letters are printed over each other. It seems like this bug appears more often when using small pixelsizes (like 12):
//Text//
int fontSize = (watermarkHeight-(4*frame));
int fontX = 2*frame;
int fontY = (result.height()-(watermarkHeight-2*frame));
int fontWidth = watermarkWidth;
QRect place(fontX,fontY,fontWidth,fontSize);
QFont font("Helvetica Neue", QFont::Light);
font.setPixelSize(fontSize);
emit log(QString::number(fontSize));
pixPaint.setFont(font);
pixPaint.setPen(QColor(255,255,255,textOpacity));
pixPaint.drawText(place,text);
Not all of these bugs appear at once! Sometimes I haven't got any bugs...
Perhaps someone had a similar bug before. Unfortunately I didn't found something like this in the internet. I didn't post a lot of code snippets because I think (and hope) that this is a gerneral problem. If you need something specific to help me, please let me know =)
I've added a example picture:
In the lineEdit I simply wrote ABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890 (look what he has done with the 7 and 9)
This small square in the lower corner of the picture should be the "ABC..." thing
The "62" looks very strange in the textBrowser
I'm using Qt 5.0.1 on a Windows 7 64Bit computer.
EDIT: Everytime after adding the first picture to the list, he's finding these warnings:
QFontEngine::loadEngine: GetTextMetrics failed ()
QWindowsFontEngine: GetTextMetrics failed ()
But when I change the height (and with it the pointSize of the font) its not emitted anymore, even with the start-parameters.
EDIT 2: Thank you for your help! I corrected my code so that he only uses correct fonts and correct sizes, but it still doesn't work. When I remove the QPainter::drawText() function it works fine (without the text). But as soon as I am adding text everything is bugged. I have something like this now:
//Text//
QList<int> smoothSizes = fontDatabase->smoothSizes("Verdana","Standard");
int fontSize = (watermarkHeight-(4*frame))*0.75;
emit log("Requested: "+QString::number(fontSize));
if(!smoothSizes.contains(fontSize)){
for(int i = 0; i<smoothSizes.length(); i++){
if(smoothSizes.at(i) > fontSize && i>0){
fontSize = smoothSizes.at(i-1);
break;
}
}
}
int fontX = 2*frame;
int fontY = (result.height()-(watermarkHeight/2)+frame);
QFont font = fontDatabase->font("Verdana","Standard",fontSize);
QFontInfo info(font);
emit log("Corrected: "+QString::number(fontSize));
emit log("Okay?: "+QString::number(info.exactMatch()));
pixPaint.setFont(font);
const QFontMetrics fontMetrics = pixPaint.fontMetrics();
if(info.exactMatch()){
pixPaint.setPen(QColor(255,255,255,textOpacity));
pixPaint.drawText(fontX,fontY+(fontMetrics.height()-fontMetrics.ascent()),text);
}
It almost sounds like you are corrupting random memory in your process, or you have a badly broken Windows install. Possibly your font request is matched by a very poorly chosen system font.
Whatever is set on a QFont is merely a request. To obtain the parameters of the actual font that was selected, you must create a QFontInfo, and get your information from there.
Imagine that you request a QFont that doesn't exist on a system, or that can't be scaled to a particular size. At some point the font object would need to morph to reflect what really happened - this would be very confusing. Thus, the QFontInfo provides the information about the font that was actually used. Think of QFontInfo as a response, and QFont as a request.
I finally found a solution: I simply updated Qt from 5.0.1 to 5.2.1, now it works. Perhaps someone has a similar bug and this post helps him. Thank you for your help!
I'm trying to display different language strings in my qt app by inserting each language into a QMap<QString, QString> so it can be re-used in several places and put into different combo Boxes across the application. I do this by
creating the QMap like so in the CTOR:
m_langMap.insert(QString::fromWCharArray(L"English"), "english");
m_langMap.insert(QString::fromWCharArray(L"Dansk"), "dansk");
m_langMap.insert(QString::fromWCharArray(L"Nederlands"), "dutch");
m_langMap.insert(QString::fromWCharArray(L"Čeština"), "czeck");
m_langMap.insert(QString::fromWCharArray(L"Slovenský"), "slovak");
m_langMap.insert(QString::fromWCharArray(L"Magyar"), "hungarian");
m_langMap.insert(QString::fromWCharArray(L"Român"), "romanian");
m_langMap.insert(QString::fromWCharArray(L"Latviešu"), "latvian");
m_langMap.insert(QString::fromWCharArray(L"Lietuvių"), "lithuanian");
m_langMap.insert(QString::fromWCharArray(L"Polski"), "polish");
m_langMap.insert(QString::fromWCharArray(L"Português"), "portuguese");
m_langMap.insert(QString::fromWCharArray(L"Español"), "spanish");
m_langMap.insert(QString::fromWCharArray(L"Français"), "french");
m_langMap.insert(QString::fromWCharArray(L"Italiano"), "italian");
m_langMap.insert(QString::fromWCharArray(L"Svenska"), "swedish");
m_langMap.insert(QString::fromWCharArray(L"Русский"), "russian");
m_langMap.insert(QString::fromWCharArray(L"Українська"), "ukranian");
m_langMap.insert(QString::fromWCharArray(L"Русский"), "russian");
m_langMap.insert(QString::fromWCharArray(L"中文"), "chinese");
m_langMap.insert(QString::fromWCharArray(L"日本語"), "japanese");
I then insert them into the combo box:
QMap<QString, QString>::const_iterator it = m_langMap.begin();
while (it != m_langMap.end())
{
ui->comboBox->addItem(it.key());
++it;
}
When the app runs, I see the following:
However, if I create a separate .ui file and insert the map the same way, I see the following (even if I include this separate Dialog class into the same application), so clearly there is no font issue as far as the App not knowing how to render the different character sets....yet I cant figure out why the first one won't render the character sets?
Can someone tell me why the first doesn't work but the second does? I checked the Designer and its Locale is set to 'C, Default' in both ui files I've shown below. I can't seem to figure out what else is causing the difference for the first not to work, and the second does work within the same application.
Thanks for any help!
The other test Dialog:
Your code is correct, but the problem is that your source file cannot contain Unicode characters - apparently it is using different coding.
Save file as UTF-8 and everything should work!
In the first screenshot the font used by the combobox is much larger than in the second screenshot. My guess is that you have changed the font either in the GUI designer or in the code and the second (working) screenshot is using the default font. It might be that when you have changed the font size, you have also changed the font to something that doesn't contain all the required Unicode characters. Try changing the font used by the combobox to something else.
I have a GUI application whose main part is a QPlainTextEdit. It is used to display a log of the application, and as such the associated text grows line by line ad infinitum.
As the application is intended to run very long, I need to limit the memory that will be allocated for this log. Therefore I want to have some maxNumLines or maxNumCharacters parameter that will make sure the history will be truncated when reached, i.e. the head lines will be removed as new lines are appended (a.k.a. log rotation).
To achieve this I found the functions
// get the associated text
QString toPlainText () const
// set the associated text
void setPlainText ( const QString & text )
Therefore something like this untested code would probably do the trick:
QString &tmp = pte.toPlainText();
while (tmp.size() > maxNumCharacters) {
// remove lines from the head of the string until the desired size is reached
// removes nothing if "\n" could not be found
tmp.remove(0, tmp.indexOf("\n")+1);
}
pte.setPlainText( tmp );
Is this the way to go to remove the first line(s) from the QPlainTextEdit? Are there probably other Qt Text GUI elements that would better fit to this task (set a maximum number of lines and truncate at the head of the list), e.g. somehow display a QStringList in which I could store the lines (s.t. I could easily erase(0))?
Or does the QPlainTextEdit eventually implement such upper bound for the size of the associated QString after all?
Apparantly the property maximumBlockCount is exactly what I need:
If you want to limit the total number of paragraphs in a QPlainTextEdit, as it is for example useful in a log viewer, then you can use the maximumBlockCount property. The combination of setMaximumBlockCount() and appendPlainText() turns QPlainTextEdit into an efficient viewer for log text.
For reference:
http://doc.qt.io/qt-5/qplaintextedit.html#maximumBlockCount-prop
I had exactly the same problem a months back, and I ended up using a QListView. Although using the model/view/delegate architecture is a bit more fiddly, it scales much better in the long run. For example once the basic architecture is in place, adding a filter that displays only error or warning entries becomes trivial, or creating a delegate so that the background of error entries are painted red is also straightforward.