Visualization Recreate the ping pong scene in 3D using ball and racket coordinates

Choosing an adequate platform C++ Scientific data visualization Limited animation capabilities Few online examples available C++ Game development Variety of online examples

OpenGL + GLUT GLUT = OpenGL Utility Toolkit –I/O operations –Opening a window and handling resizes –Executing the actual OpenGL code –Mouse controls and keyboard interaction –Façade functions that combine several basic OpenGL routines

OpenGL Rendering Pipeline Listing of points, lines and basic primitives Transformations, lighting and clipping non-visible parts from the scene Conversion into fragments, each fragment square corresponds to a pixel in the frame buffer.

Drawing the table Within glBegin(GL_QUADS) block –Specifies that quadrangle points follow below Using glVertex3f-function –Calling this function for every angular point In combination with glNormal3f –Specifies the direction of the normal glNormal3f( 1.0f, 0.0f, 0.0f); // Normal Facing Right glVertex3f( 1, -1, -1);// Bottom Right glVertex3f( 1, 1, -1);// Top Right glVertex3f( 1, 1, 1);// Top left glVertex3f( 1, -1, 1);// Bottom left

Animating the ball movement Only possible to draw spheres with void glutSolidSphere(GLdouble radius, GLint slices, GLint stacks); Specifing the location: multiplying the table matrix with a matrix that moves the object glTranslatef(x, y, z); Then draw the ball Do this for every 3D ballcoordinate

Displaying the rackets Same strategy as with the ball movement Drawing a cylinder at a specified position Coordinates are in a separate CSV file

Animation (1) Key frame animation Movie is 25 frames per second (40 ms) Animation has a 10 ms refresh rate At least 4 times the coordinates as in the movie Redrawing the ball using an (interpolated) xyz-coordinate (generated in WP4)

Animation (2) Regulating speed: skipping coordinates List of coordinates fuels: –Rewind/forward –Pause/play –Tracers –Special camera positions

Camera placement (1) Use the Utility Library (GLUT) routine gluLookAt() to define a line of sight –Encapsulates a series of rotation and translation commands gluLookAt(4.0, 2.0, 1.0, 2.0, 4.0, -3.0, 2.0, 2.0, -1.0); Fully adjustable camera angles: –Rotating the view (around all axis) –Dragging table (up, down, left, right) –Zooming Cam. posUp vectorCenter (ref. point)

Camera placement (2) First-person ball tracking using recently displayed coordinates

Functionality Continuous rotation Tracers –Use already displayed coordinates and draw a stippled line between each pair

Demo Using mouse & keyboard controls to interpret commands

Improvements Anti-aliasing Enhancing the coordinates by using a physics engine –Calculating accurate speed –Simulating gravity –Simulating air resistance

Conclusion Visualization runs smoothly Success or failure depends on accurate 3D coordinates