POINTS_DISPLAY_OPEN_GL
Display 2D Pointsets Using OpenGL

POINTS_DISPLAY_OPEN_GL is an executable C++ program, using double precision arithmetic, that reads the name of a data file containing a list of 2D point coordinates, reads the data, and displays the points using OPEN_GL.

POINTS_DISPLAY_OPEN_GL also creates an ASCII PPM file of the screen, so that the graphics may be saved for later analysis.

Usage:

points_display_open_gl data.txt

reads the data in data.txt and displays a plot of the points.

Related Data and Programs:

BOX_PLOT is a MATLAB program which can color in specified entries of a checkerboard, corresponding to pairs of integer data.

FLOOD_OPEN_GL is a C program which allows a user to select a region and flood it with color, using OpenGL, by Art Wetzel.

OPEN_GL is used to handle the graphics display.

PLOT_POINTS is an executable FORTRAN90 program which can read a file of point coordinates and make a PostScript image of them.

POINTS_DISPLAY is a MATLAB program which can read a file of coordinates of points, and display an image of the points in a MATLAB graphics window.

POINTS_01_PLOT is a MATLAB program which can read a file of coordinates for points in the unit square, and display an image of the points.

PPMA is the format used for the output files created by POINTS_DISPLAY_OPEN_GL.

TABLE is the format used for the input files to POINTS_DISPLAY_OPEN_GL.

TABLE_BARPLOT_PPMA is an executable FORTRAN90 program which reads a table file and creates a PPMA bargraph of the data.

TABLE_DELAUNAY is an executable FORTRAN90 program which computes the Delaunay triangulation of a set of points.

TABLE_DIAPHONY is an executable FORTRAN90 program which computes the diaphony of a set of points stored in a table file.

TABLE_IO is a C++ library which supplies the routines used to read the TABLE file.

TABLE_VORONOI is an executable C++ program which can be used to compute information about the Voronoi diagram of the points.

TRI_MESH_DISPLAY is a MATLAB program which reads data defining a triangular mesh of a 3D surface and displays it.

TRIANGULATION_DISPLAY_OPEN_GL is an executable C++ program which reads files defining a triangulation and displays an image using Open GL.

XY is a data directory which contains some examples of 2D pointsets.

Reference:

1. Edward Angel,
   Interactive Computer Graphics, a Top-Down Approach with OpenGL,
   Addison-Wesley, 2000,
   ISBN: 0-201-38597-X,
   LC: T385.A514.
2. Renate Kempf, Chris Frazier, editors,
   OpenGL Reference Manual,
   Fourth Edition,
   Addison-Wesley, 2004,
   ISBN: 032117383X,
   LC: T385.O642
3. Mason Woo, Jackie Neider, Tom Davis,
   OpenGL Programming Guide,
   Addison-Wesley, 1997,
   ISBN: 0-201-46138-2,
   LC: T385.N435
4. Richard Wright, Michael Sweet,
   OpenGL Superbible,
   Third Edition,
   Sams, 2004,
   ISBN: 0672326019,
   LC: T385.W73
5. http://www.opengl.org/
   The official OpenGL site.

Source Code:

• points_display_open_gl.C, the source code.
• points_display_open_gl.csh, commands to compile the source code.

Examples and Tests:

• lsup_303.out, the printed output in response to the command:

  
              points_display_open_gl lsup_303.xy

• lsup_303.xy, 303 points that outline Lake Superior.
• lsup_303.png, a PNG image of the screen generated by Open GL. (This file was created by applying convert to the ASCII PPM file created by POINTS_DISPLAY_OPEN_GL.

List of Routines:

• MAIN is the main program for POINTS_DISPLAY_OPEN_GL.
• CH_EQI is true if two characters are equal, disregarding case.
• CH_TO_DIGIT returns the integer value of a base 10 digit.
• DISPLAY generates the graphics output.
• DTABLE_DATA_READ reads the data from a real TABLE file.
• DTABLE_HEADER_READ reads the header from a real TABLE file.
• FILE_COLUMN_COUNT counts the number of columns in the first line of a file.
• FILE_ROW_COUNT counts the number of row records in a file.
• I3MAT_FLIP_COLS swaps the columns of an I3MAT.
• MYINIT initializes OpenGL state variables dealing with viewing and attributes.
• PPMA_WRITE writes the header and data for an ASCII portable pixel map file.
• PPMA_WRITE_DATA writes the data for an ASCII portable pixel map file.
• PPMA_WRITE_HEADER writes the header of an ASCII portable pixel map file.
• R8_MAX returns the maximum of two R8.
• R82VEC_MAX returns the maximum value in a R82VEC.
• R82VEC_MIN returns the minimum value in a R82VEC.
• S_LEN_TRIM returns the length of a string to the last nonblank.
• S_TO_R8 reads an R8 from a string.
• S_TO_R8VEC reads an R8VEC from a string.
• S_WORD_COUNT counts the number of "words" in a string.
• TIMESTAMP prints the current YMDHMS date as a time stamp.
• TIMESTRING returns the current YMDHMS date as a string.

You can go up one level to the C++ source codes.