Posts tagged with “papervision3d”

PV3D sound visualization

April 21st, 2008

Playing with computeSpectrum() and PV3D 2.0 alpha (Great White). The mesh reacts to sound by having its vertices moved along the Z axis (X and Y coordinates are fixed). Had a problem with FlatShadeMaterial failing to render on regions of coplanar faces; small creases were made in the mesh to fix it.

Sound analysis was made with SoundMixer.computeSpectrum(), FFTMode set to true (a frequency spectrum results in a more interesting visualization) and stretchFactor set to 4. Increasing the stretchFactor value means analyzing a smaller frequency range of the sound —thus ignoring non-audible high frequencies. The 16×16 vertex grid represents the average values of left and right channels.

Music Is Music As Devices Are Kisses Is Everything (5:20) by 65daysofstatic (from the 2007 album The Destruction Of Small Ideas) is the song; a nice fit for this visualization because of the contrasting quiet and loud parts —the visualization of the piano notes in the quiet sections is very clear.

View SWF (5MB, move mouse on X direction to change rotation, music plays 10 times)

Update: comments closed because of spam.

Update #2: this experiment was featured on PV3D blog — 9 Cool Experiments in 3D.

PV3D ribbons

April 13th, 2008

This week I worked on converting last week’s Particles and trails code to 3 dimensions, using the Effects branch of Papervision3D.

The final SWF runs smoothly at 30fps on my computer, and initially uses about 5MB of memory as measured by System.totalMemory. The biggest challenge in this project was fixing a memory leak that occurred whenever a ribbon was removed from the scene. If you run into this problem when removing a DisplayObject3D, remember to:

public function destroy():void
    geometry.faces = [];
    geometry.vertices = [];

Each ribbon has 3 life phases:

  1. Growth: the ribbon grows until it reaches 120 vertices;
  2. Stability: the ribbon keeps moving but older faces and vertices are removed, keeping vertex count equal to 120;
  3. Removal: the ribbon stops moving and 2 vertices and 2 faces are removed frame by frame until it reaches zero vertices and zero faces.

The applied material is a simple FlatShadeMaterial with a moving light source. Finally, a BitmapLayerEffect with BlurFilter was applied and the viewport.blendMode was set to BlendMode.ADD.

View animation (move mouse to change camera rotation)