Jit.gl.sketch controlling question

Hi Bas,

For the next version of Jitter we're working on making it easier to group and manage rendering to texture. Sorry that this is a tricky thing to accomplish currently. For the meantime, there's a few things worth noting on this thread:

- sketch capturing to texture. As highlighted by an off forum email message. Sketch and capturing doesn't work with immediate mode.

- any object, not just sketch, is captured to a texture by setting the capture attribute, not the draw to. However this can present a problem for capturing multiple objects to the same texture, or the same object multiple times.

The current way I would recommend around both of these issues would be to use the little known begin_capture and end_capture messages to jit.gl.texture, in conjunction with the also little known jit.gl.object's drawimmediate method. Below is an example Javascript, which should translate to Java easily.

Hope this helps.

var window = new JitterObject("jit.window", "foo");
var render = new JitterObject("jit.gl.render", "foo");

var gridshape = new JitterObject("jit.gl.gridshape", "foo");
gridshape.automatic = 0;

var sketch = new JitterObject("jit.gl.sketch", "foo");
sketch.automatic = 0;

var texture = new JitterObject("jit.gl.texture", "foo");
texture.dim = [1024, 768];

var videoplane = new JitterObject("jit.gl.videoplane", "foo");

var firsttime = 1;

function bang()
{
    if (firsttime) { // initialize once
        render.erase();
        render.drawswap();
        firsttime = 0;
    }

    // sets our texture as the current context, and erases it
    texture.begin_capture();

    // let's change the background color
    // sketch in immediate mode doesn't work inside the capture
    // so instead, we'll use sketch's drawimmediate method
    // which uses the current commandlist
    sketch.reset();
    sketch.glclearcolor(0.1,0.5,0.1,1.);
    sketch.glclear();
    sketch.glenable("lighting");
    sketch.drawimmediate();

    // now let's draw our gridshape a few times
    // once with lighting enabled, once without
    gridshape.position = [1.,1.,0];
    gridshape.lighting_enable = 1;
    gridshape.drawimmediate();

    gridshape.position = [-1.,-1.,0];
    gridshape.lighting_enable = 0;
    gridshape.drawimmediate();

    // finishes capturing
    texture.end_capture();

    // render the rest of the scene, with our texture on a video plane
    render.erase();
    videoplane.jit_gl_texture(texture.name);
    render.drawswap();
}