Synchronize an QOpengl line with audio file
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@HW-Developer
well did u subclass QOpenglWidget ?
If yes, you can just add a slot to it like
public slots:
void PositionChanged( int pos) ;and in cpp
void yourclassname:: PositionChanged( int pos) {
change the variable that controls the red line.
}@mrjj for example if we have this code to draw the red line
glColor3f(1.0, 0.0, 0.0); glBegin(GL_LINES); glVertex3f(-1 + (redLine*scaleFactor), 1 + -(0 * 0.016), -1.0); glVertex3f(-1 + (redLine*scaleFactor), 1 + -(130 * 0.016), -1.0); glEnd();//scaleFactor is a float variable which determines the space before the red line
//redline is a float variable = 320 + 160;and i create the positionChanged(int position) methode, what should i change using the position variable?
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@mrjj for example if we have this code to draw the red line
glColor3f(1.0, 0.0, 0.0); glBegin(GL_LINES); glVertex3f(-1 + (redLine*scaleFactor), 1 + -(0 * 0.016), -1.0); glVertex3f(-1 + (redLine*scaleFactor), 1 + -(130 * 0.016), -1.0); glEnd();//scaleFactor is a float variable which determines the space before the red line
//redline is a float variable = 320 + 160;and i create the positionChanged(int position) methode, what should i change using the position variable?
@HW-Developer
I would assume redLine variable ? -
@HW-Developer
I would assume redLine variable ? -
@mrjj When i use redLine =0, it gives me this result:
so 160 is the space between the small grey lines
and 320 is just a number that i added so the red line will be in the same line with my slider
@HW-Developer
so the redline default offset is 320+160.
so if you add to that, it will move the redline.
Do you mean to hook up the slider so it moves the redline or what is task? -
@HW-Developer
so the redline default offset is 320+160.
so if you add to that, it will move the redline.
Do you mean to hook up the slider so it moves the redline or what is task? -
@mrjj The slider was my first test so to have the same result i did have with my slider i initialize the red line on the same line with that slider so when the audio is playing, they will be moving in the same time
@HW-Developer
ok.
so now you want a method in QOpenglWidget that also moves the redLine ? -
@HW-Developer
ok.
so now you want a method in QOpenglWidget that also moves the redLine ? -
@mrjj Yes that's right
@HW-Developer
Ok, i assumed you subclassed it ?
like
class MyGLWidget : public QOpenGLWidget ...so you can just add a new method to it to alter the redLine variable.
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@HW-Developer
Ok, i assumed you subclassed it ?
like
class MyGLWidget : public QOpenGLWidget ...so you can just add a new method to it to alter the redLine variable.
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@mrjj Yes of course i already did what is necessary to have the drawing ruler that i upload it above
@HW-Developer
ok but you question was
" how to create positionchanged method in my QOpenglWidget class,"
so i must be missing something you ask about ?
(if you already did make such method) -
@HW-Developer
ok but you question was
" how to create positionchanged method in my QOpenglWidget class,"
so i must be missing something you ask about ?
(if you already did make such method) -
@mrjj I already draw the qopenglwidget but I did not synchronize it with the audio file using positionchanged method that I did ask you about
hi
well you can hook up the AUDIO positionchanged
signal to your own method (slot)
using connect.
http://doc.qt.io//qt-5/signalsandslots.htmlso it will directly call your method when it changes.
