optimization for a dynamic texture

[Rubis]

Hi,

 

I want to show data on a mesh ( an histogram, one axis is data , other is time). I use a dynamic texture and the render loop to slide curent content by one column, then i create an array  to stock my data then i rewrite the content of the array on the first line of my texture context.

 

This is an exemple ( playground doesn't work) of the structure. This structure work  but i don't thing i have to touch two time conText with the same function( cost FPS). I'm completly conscient that a better way exist like paste each pixel in image data, but before i need your suggestions.

var dynText = new BABYLON.DynamicTexture("dino",512,scene);var conText = dynText.getContext();var size = dynText.getSize();var pixelIndex =0;// render loopengine.runRenderLoop(function () {	// array of my data, each loop i've got completly new data [0,1]	donnee = ligne();	//slide by one all my previous data, NOTICE the one at the end 	conText.putImageData(conText.getImageData(0, 0, size.width, size.height), 0, 1);		// write the first line with my data	imageData = conText.getImageData(0, 0, size.width, size.height);		for(var j =0 ;j<size.width;j++){		pixelIndex = j*4;		// grey scale		imageData[pixelIndex ] = donnee[j]*255; // red one		imageData[pixelIndex + 1 ] = donnee[j]*255; // green oen		imageData[pixelIndex + 2] = donnee[j]*255; // blue one		imageData[pixelIndex + 3] = 255; // alpha	}		conText.putImageData(imageData,0,0);        dynText.update();			        scene.render();});

[jerome]

Well, generating a new texture each frame is not such a good idea because it's really costly in fps

 

... and human eyeballs can't reasonably follow/understand data evolving 60 times per second

 

That said, if you want to display data with graphics in a 3D engine, why making a 2D texture instead of using directly 3D shapes (planes, boxes, etc) ?

 

If you still want a 2D texture applied to a 3D mesh, I would suggest to re-generate it at some frequency relative to the data refresh only ( with setInterval() ) instead of at each frame.

[jahow]

Hey,

 

It seems you have simpler solutions at hand. As Jerome said, using meshes instead of a dynamic texture could prove useful.

 

If you want to stick to a DynamicTexture, then I'd avise rect(x, y, width, height) to draw stuff, instead of put/getImageData. Currently your logic is:

• getImageData of the whole texture
• putImageData shifted 1 pixel
• getImageData of the whole texture
• draw new first line in image data
• putImageData at the same place

Why not:

• getImageData of the whole texture
• putImageData shifted 1 pixel
• draw new first line with rect()

Or even:

• save new data in an array, pushing older data back
• draw every line from the array using rect()

And of course only update when necessary!