Data Visualization GraphicsView/Scene/Item Design

[vgrunert]

Hi,

I am working on a custom data visualization program.

My question is how to display/map/transform the data from a model to the view/scene in order to:

1. Get correct results
2. Minimize computational effort

So far, in order to draw a scatterplot, I came up with two different approaches:

Here is a short pseudocode:

//initialize data 
A[5], B[5]
i=0
 
//fill vectors with randon data
while (i < 5)
A[i] = rand(10);
B[i] = rand(10);
i++; 
myGraphicsScene->addRect(A[i], -B[i], 5, 5);
 
//set scene
myGraphcisView->setScene(myGraphicsscene)

//initialize data 
A[5], B[5]
i=0

//fill vectors with randon data
while (i < 5)
A[i] = rand(10);
B[i] = rand(10);
i++; 
myGraphicsScene->addRect(A[i], -B[i], 5, 5);

//set scene
myGraphcisView->setScene(myGraphicsscene)

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Since the data is not scaled to the scene coordinates there are two different ways to plot the data (from my current understanding):

1. Transform/multiply the data with some factor to expess the values in terms of scene coordinates
2. Fit the scene to the data (myScene->sceneRect(0,-max(B), max(A), max(B)) and then fit the scene to the graphicsview using myview -> fitInView(myscene)

Now from your experience, which approach would you recommend?
Are there another way to approach the problem?

Thank you many times,

Vincent