Slowing down interpolation in ProScene

jimthree

Slowing down interpolation in ProScene

in Contributed Library Questions • 2 years ago

Hi,

I've been implementing the ridiculously awesome ProScene into one of my projects, but I've hit a stumbling block. I have a large scene, in which i want the camera to move between two keyframes a straight line. ProScene allows me to do this very easily, I just hit CTRL+1 where I the path to start and again where I want it to end. that bit works fine!

However, I can't control the speed at which the camera interpolates between the two keyframes. I've tried to implement setInterpolationSpeed() but the way I've done it isn't attaching to the pre-defined interpolaters/cameras assigned to the keys 1-5 which I'm using.

Here is my code, can anyone give me direction on this?

thanks

Jim

import remixlab.proscene.*;
import javax.media.opengl.*;
import codeanticode.glgraphics.*;
Scene scene;
KeyFrameInterpolator kfi;
GLModel grid;
void setup() {
size(screen.width-100, screen.height-100, GLConstants.GLGRAPHICS);
//Scene instantiation
scene = new Scene(this);
scene.setAxisIsDrawn(false);
scene.setGridIsDrawn(false);
scene.setRadius(15000);
scene.camera().showEntireScene();
//try to change the the speed of interpolation
kfi = new KeyFrameInterpolator(this);
kfi.setInterpolationSpeed(100.0f);
//create Grid GLmodel
drawgrid(85,100,20);
}
void draw()
{
GLGraphics renderer = (GLGraphics)g;
renderer.beginGL();
grid.render();
renderer.endGL();
}
void drawgrid(float spacing, int gridsize, float gridStroke)
{
int gridverts = gridsize*4;
grid = new GLModel(this, gridverts+4, LINES, GLModel.STATIC);
grid.initColors();
grid.beginUpdateVertices();
for (int i = 0; i < gridverts+4; i=i+4)
{
grid.updateVertex(i,-(gridverts*(spacing/2)), (i*spacing)-((gridverts/2)*spacing), 0);
grid.updateVertex(i+1,(gridverts*(spacing/2)), (i*spacing)-((gridverts/2)*spacing), 0);
grid.updateVertex(i+2,(i*spacing)-((gridverts/2)*spacing),-(gridverts*(spacing/2)), 0);
grid.updateVertex(i+3,(i*spacing)-((gridverts/2)*spacing),(gridverts*(spacing/2)), 0);
}
grid.endUpdateVertices();
grid.beginUpdateColors();
for (int i = 0; i < gridverts+4; i=i+4)
{
if (i@ == 0)
{
grid.updateColor(i, 255, 255, 255, gridStroke+30);
grid.updateColor(i+1, 255, 255, 255, gridStroke+30);
grid.updateColor(i+2, 255, 255, 255, gridStroke+30);
grid.updateColor(i+3, 255, 255, 255, gridStroke+30);
}
else if(i == 0)
{
grid.updateColor(i, 255, 255, 255, gridStroke+15);
grid.updateColor(i+1, 255, 255, 255, gridStroke+15);
grid.updateColor(i+2, 255, 255, 255, gridStroke+15);
grid.updateColor(i+3, 255, 255, 255, gridStroke+15);
}
else
{
grid.updateColor(i, 255, 255, 255, gridStroke);
grid.updateColor(i+1, 255, 255, 255, gridStroke);
grid.updateColor(i+2, 255, 255, 255, gridStroke);
grid.updateColor(i+3, 255, 255, 255, gridStroke);
}
}
grid.endUpdateColors();
}

Replies(4)

nakednous

Re: Slowing down interpolation in ProScene

2 years ago

Hi,

since you are using the default camera paths (e.g., CTRL+1 combo) it makes sense to just change the interpolation speeds of them. I have modified the BasicUse example to interactively change the interpolation speed of the first camera path. Please have a look:

import remixlab.proscene.*;
Scene scene;
KeyFrameInterpolator kfi;
void setup() {
size(640, 360, P3D);
scene = new Scene(this);
}
void draw() {
fill(204, 102, 0);
box(20, 30, 50);
}
void keyPressed() {
kfi = scene.camera().keyFrameInterpolator(scene.path('1'));
if (kfi == null)
return;
if( key == 'u' || key == 'v' ) {
if ( key == 'u')
kfi.setInterpolationSpeed(kfi.interpolationSpeed()-0.25f);
if ( key == 'v')
kfi.setInterpolationSpeed(kfi.interpolationSpeed()+0.25f);
println("interpolation speed = " + kfi.interpolationSpeed());
}
}

If you want to set you own KeyFrameInterpolators have a look at the FrameInterpolation example. You may also have a look at the KeyFrameInterpolation class reference.

Hope it helps, otherwise keep posting :)

Jean Pierre

nakednous

Re: Re: Slowing down interpolation in ProScene

2 years ago

another possibility would be if you know the position and orientation of your key frames in advanced, such in the CameraInterpolation example. In this case, you might also defined the interpolation speed directly at the setup by adding at its end:

scene.camera().keyFrameInterpolator(1).setInterpolationSpeed(mySpeed);

where mySpeed is a float defining your speed. I tried it for the CameraInterpolation example and it worked

Jean Pierre

jimthree

Re: Slowing down interpolation in ProScene

2 years ago

That's Great, Thanks Jean Pierre!

Your KeyPressed() example works when I implement it in my sketch, but whenever I try to move the setInterpolationSpeed(mySpeed) code into the setup function (so that it is in effect from the launch of the sketch, rather than requiring input) I get a null pointer exception, and I can't work out why...

I have tried: (I didn't expect the first one to work, but I thought the second one would)

void setup() {
size(screen.width-100, screen.height-100, GLConstants.GLGRAPHICS);
//Scene instantiation
scene = new Scene(this);
//try to change the the speed of interpolation
kfi = scene.camera().keyFrameInterpolator(scene.path('1'));
scene.camera().keyFrameInterpolator(1).setInterpolationSpeed(0.1f);
//create Grid GLmodel
drawgrid(85,100,20);
}

and

void setup() {
size(screen.width-100, screen.height-100, GLConstants.GLGRAPHICS);
//Scene instantiation
scene = new Scene(this);
//try to change the the speed of interpolation
kfi = scene.camera().keyFrameInterpolator(scene.path('1'));
kfi.setInterpolationSpeed(0.1f);
//create Grid GLmodel
drawgrid(85,100,20);
}

I'll keep working on this to see if I can solve it myself, but if you can see what I'm doing wrong then please shout! :)

Jim

nakednous

Re: Re: Slowing down interpolation in ProScene

2 years ago

You need to add first a key frame to a path before configuring it (otherwise the kfi is null). For instance:

               
                //add the current camera position to the path:
                scene.camera().addKeyFrameToPath(1);
                //now modify it
                float mySpeed = 3.5f; //default speed is 1
                
                 scene.camera().keyFrameInterpolator(1).setInterpolationSpeed(mySpeed);
               
You can also set the camera position and orientation manually before calling addKeyFrameToPath:

                 
                  scene.camera().setPosition(new PVector(80,0,0));
                  scene.camera().lookAt( scene.camera().sceneCenter() );
                 Hope that helps!
Jean Pierre

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