package oplot

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Module Oplot.PltSource

Main Oplot functions

This module contains all functions for defining and rendering plots.

Sourcetype plot_device =
  1. | X11
  2. | GL
  3. | FIG
Sourcetype points = Points.point list
Sourcetype axis
Sourcetype image
Sourcetype latex
Sourcetype text
Sourcetype imatrix = int array array
Sourcetype fmatrix = float array array
Sourcetype grid = fmatrix * view3 * bool
Sourcetype surf3d = fmatrix * fmatrix * fmatrix * view3 * bool
Sourcetype curve3d = Points.point3 list * view3
Sourcetype move3d
Sourcetype gllist
Sourcetype color = {
  1. r : float;
  2. g : float;
  3. b : float;
}
Sourceval black : color
Sourceval white : color
Sourceval red : color
Sourceval green : color
Sourceval blue : color
Sourceval yellow : color
Sourceval cyan : color
Sourceval magenta : color
Sourcetype align =
  1. | CENTER
  2. | LEFT
  3. | RIGHT

Defining plot objects

'Defining' means computing the coordinates of the points and lines to display, but not actually displaying them. We call a "sheet" a list of objects to be displayed.

Sourcetype plot_object =
  1. | Points of points
    (*

    A list of points.

    *)
  2. | Lines of points list
    (*

    The points of each sublist are joined by a line segment.

    *)
  3. | Poly of points
    (*

    Closed polygonal line.

    *)
  4. | View of view option
    (*

    Indicate the x-y range to display.

    *)
  5. | Axis of axis
    (*

    Axis with divisions.

    *)
  6. | Color of color
    (*

    Indicate the color to draw subsequent objects.

    *)
  7. | Text of text
    (*

    Position a text at some (x,y) coordinate.

    *)
  8. | Matrix of imatrix * view option
    (*

    Checkboard-like matrix view with 0-255 greyscale.

    *)
  9. | Grid of grid * gllist
    (*

    3D mountain-like representation of a matrix.

    *)
  10. | Surf3d of surf3d * gllist
    (*

    3D parametric surface.

    *)
  11. | Curve3d of curve3d * gllist
    (*

    3D points joined by line segments.

    *)
  12. | Move3d of move3d
    (*

    Animate the 3D object by a uniform rotation.

    *)
  13. | Pause of int
    (*

    Display the current state of the sheet, and wait before displaying next object, but don't stop animation in the opengl window. This only works for interactive displays using the GL device.

    *)
  14. | Freeze of int
    (*

    Display the current state of the sheet and suspend all display for the given time.

    *)
  15. | Clear of color
    (*

    Clear graphics.

    *)
  16. | Adapt of (view option * plot_object option) ref * view option -> plot_object
    (*

    Any object that needs to adapt itself to the current View.

    *)
  17. | User of view -> plot_device -> unit
    (*

    Execute any user-defined program.

    *)
  18. | Sheet of plot_object list
    (*

    Group plot objects.

    *)

2D objects

Helper functions for creating 2D plot objects

Sourceval point : (float * float) -> Points.point

A single point (x,y).

Sourceval axis : float -> float -> plot_object

axis x0 y0 creates an Axis object with two axis crossing at the point (x0,y0).

Sourceval parametric_plot : (float -> float) -> (float -> float) -> ?pas:float -> ?adapt:bool -> float -> float -> plot_object

parametric_plot fx fy t0 t1 computes a parametric curve given by the points (fx(t), fy(t)), for t varyingn from t0 to t1. If adapt is true, the step will adapt to the arc-length of the curve.

Sourceval point_plot_f : (float -> float) -> ?pas:float -> float -> float -> plot_object

point_plot_f f x0 x1 computes a subset of the graph of the function f obtained by isolated points with a fixed horizontal step.

Sourceval line_plot_f : (float -> float) -> ?pas:float -> float -> float -> plot_object

Similar to point_plot_f but the points are joined by line segments.

Sourceval plot : (float -> float) -> ?pas:float -> float -> float -> plot_object

Alias for line_plot_f.

Sourceval adapt_plot : (float -> float) -> ?pas:float -> float -> float -> plot_object

Similar to line_plot_f, but the plot will be dynamically cropped to the current view object. It returns an Adapt object.

Sourceval anim_plot : (float -> float -> float) -> ?pas:float -> ?t0:float -> ?t1:float -> float -> float -> plot_object

If f is a function two parameters t and x, then anim_plot f x0 x1 will generate an animation of the graph of the functions f t for t evolving with real time. The resulting object is of type User.

Sourceval text : string -> ?size:int -> ?align:align -> float -> float -> plot_object

text s x y draws the string s at the position (x,y).

Sourceval latex : string -> ?size:int -> ?align:align -> float -> float -> plot_object

Similar to text but the rendered text is the result of LaTeX compilation of the given string.

Sourceval view : float -> float -> float -> float -> plot_object

view x0 y0 x1 y1 creates a View object indicating the bounding box for subsequent drawings.

3D objects

Helper functions for creating 3D plot objects

Sourceval point3 : (float * float * float) -> Points.point3

A single 3D point (x,y,z).

Sourceval surf3d_plot : (float -> float -> float) -> (float -> float -> float) -> (float -> float -> float) -> ?width:int -> ?height:int -> ?wire:bool -> float -> float -> float -> float -> plot_object

surf3d_plot fx fy fz u0 v0 u1 v1 computes the parametric surface spanned by the map (u,v)->(fx(u,v), fy(u,v), fz(u,v)) when (u,v) varies in the range [u0,u1] ✕ [v0,v1].

Sourceval grid_plot : (float -> float -> float) -> ?wire:bool -> ?width:int -> ?height:int -> float -> float -> float -> float -> plot_object

grid_plot f x0 y0 x1 y1 computes the graph of the function f of two variables x y, when (x,y) varies in the range [x0,x1] ✕ [y0,y1].

Other objects

Sourceval color : float -> float -> float -> plot_object

Specifies the RGB color for subsequent drawings.

Sourceval freeze : int -> plot_object

freeze t creates a Freeze for t ms.

Sourceval pause : int -> plot_object

pause t creates a Pause for t ms.

Sourceval rotate : float -> float -> float -> float -> float -> plot_object

rotate x y z theta t rotates the 3D scene with angular velocity theta (in radians) aroung the axis (x,y,z), during time t.

Displaying the plot objects

Various devices can be used to render the plots.

Sourcetype user_device
Sourceval display : ?dev:user_device -> ?fscreen:bool -> ?output:string -> plot_object list -> unit

Initialize the graphics device and display the plot objects

Available devices

Software rendering in a separate window

Hardware (opengl) rendering in a separate window. This is the default

Render to an xfig file

Open in the xfig program, if present

Render to an EPS (encapsulated postscript) file

Render to a PDF (portable document format) file

Render to EPS and open with a postscript viewer like gv

Render to a BMP image

Open in an image viewer

Rendering parameters

Sourceval resize_window : int -> int -> unit
Sourceval get_gl_scale : unit -> float

The GL_SCALE is used to accomodate for HI-DPI screens. A "normal" screen of DPI about 110 should have GL_SCALE=1. A HI-DPI screen can typically have a scale of 2 or 2.5; on linux the GL_SCALE is detected at startup. It can be modified by the user.

Sourceval set_gl_scale : float -> unit
Sourceval quit : ?dev:plot_device -> unit -> unit

Close the current rendering window and clear the temporary directory

Sourceval get_tmp_dir : unit -> string

Drawing specific objects

These functions should not be used interactively, because they necessitate the graphics window to be already opened by display; but they can be interesting when programming a User object.

Sourceval set_color : ?dev:plot_device -> color -> unit
Sourceval object_plot : ?addcounter:bool -> dev:plot_device -> plot_object -> view option -> unit

Draw a single object, but not a Sheet. The device must have been initialized before.

If addcounter is true (default) the object will be considered as a new element of the currently displayed sheet; otherwise, it will be considered as being part of the currently displayed object: this only affects the Pause mechanism.

Sourceval elapsed : unit -> int

Time elapsed from the openning of the opengl window

Sourceval user_flush : plot_device -> unit

Synchronize graphics output by swapping back and front buffers. Hence two consecutive calls will result in flicker. See copy_back_buffer.

Sourceval copy_back_buffer : unit -> unit

Copy backbuffer to front buffer. If I use this intensively I can really hear my graphics card...