Fluid Definition and 1000 Threads

FLUID (Fast Light User Interface Designer) is a graphical editor and GUI builder that is used to produce FLTK source code. FLUID edits and saves its state in text .fl files, which can be edited in a text editor for finer control over display and behavior.After designing the application, FLUID compiles the .fl file into a .cxx file, which defines all the objects from the .fl file, and an .h file, which declares all the global ones. FLUID also supports localization of label strings using message files and the GNU gettext or POSIX catgets interfaces.

A simple program can be made by putting all non-interface code (including a main function) into the .fl file, thus making the .cxx file a single source file to compile. Most programs are more complex than this, so other .cxx files can be written that call the FLUID functions. These .cxx files must #include the .h file, or they can #include the .cxx file so it still appears to be a single source file.
Normally the FLUID file defines one or more functions or classes, which output C++ code. Each function defines one or more FLTK windows, and all the widgets that go inside those windows.
Widgets created by FLUID are "named", "complex named", or "unnamed". A named widget has a legal C++ variable identifier as its name (i.e. only alphanumeric and underscore), and is defined by a global variable or class member that will point at the widget after the function defining it is called. A complex named object has punctuation such as '.' or '->' or any other symbols in its name. In this case, FLUID assigns a pointer to the widget to the name, but does not attempt to declare it. This can be used to get the widgets into structures. An unnamed widget has a blank name and no pointer is stored.
Widgets may either call a named callback function that one writes in another source file, or one can supply a small piece of C++ source and FLUID will write a private callback function into the .cxx file.

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  1. R

    How do you compute the circulation of this fluid (path integrals)

    Homework Statement A fluid as velocity field F(x, y, z) = (xy, yz, xz). Let C denote the unit circle in the xy-plane. Compute the circulation, and interpret your answer.Homework Equations The Attempt at a Solution Since the unit circle is a closed loop, I assumed that ∫ F * dr = 0 (the ∫ symbol...
  2. X

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  3. C

    Fluid Mechanics textbook Recommendations - 1st year Mech Eng

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  4. T

    Divergence of velocity of incompressible fluid in uniform gravity

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  5. M

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  6. R

    Fluid Mechanics: Compressible Fluids, density function

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  7. M

    Drip chamber pressure effect effect in fluid administration

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  8. T

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  9. T

    Fluid flow through a pipe - Conservation of mass and/or momentum?

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  10. K

    Van de Waals fluid in Free energy, Enthelpy representations

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  11. D

    Question about fluid dynamics (calculating concentration)

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  12. T

    Fluid mechanics - Conservation of mass problem

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  13. M

    Adding stirring force acting on the fluid

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  14. T

    Plasma Fluid Mechanics - Convective Derivatives

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  15. D

    Question about fluid flow and pressure in pipes

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  16. A

    FLuid Flow through a Divergent Section

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  17. Astronuc

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  18. J

    Fluid Mechanics Problem Creating a Mesh

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  19. B

    Basic Fluid Dynamics: Calculating Exit Velocity & Mass Flow Rate

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  20. J

    Probability fluid velocity and quantum entanglement question

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  21. S

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  22. M

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  23. S

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  24. L

    Calculating the average divergence of the flow of fluid in a box.

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  25. P

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  26. E

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  27. M

    Understanding bulk fluid motion under Lorentz force

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  28. P

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  29. M

    Predicting Lorentz force fluid particle trajectories

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  30. P

    Fluid mechanics: Flow and velocity of a fluid

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  31. P

    Weight of a fluid when I put my finger in it

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  32. B

    Need help on basic fluid volume calculation

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  33. B

    I need help with a Fluid Mechanics problem

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  34. E

    What causes an increase in boundary layer thickness in fluid flow?

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  35. J

    Can any one help with this Fluid mechanics question please?

    Homework Statement A shaft of diameter 74.9mm rotates at 1400rpm in a bearing which is of diameter 75.03 mm and 75mm in length. The annular space between the shaft and the bearing is filled with oil of viscosity 0.096 kg/ms.By assuming a uniform velocity gradient in the oil, determine the...
  36. V

    Idealized Fluid: Pressure & Force Tangential to Surface

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  37. T

    What Are the Best Fluid Mechanics Textbooks for Aspiring Students?

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  38. K

    Fluid mechanics: defition of shear flow [rate of deformation tensor]

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  39. tomwilliam2

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  40. E

    Fluid Statics - Forces on Submerged Surface?

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  41. P

    Question about fluid mechanics

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  42. R

    Rotating Bucket Dynamics: Oil vs. Water Surface Shapes

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  43. G

    What are some alternatives to lubricant oil for industrial testing purposes?

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  44. D

    What is the Tension in the String Holding a Submerged Cork?

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  45. S

    Defining Low and High Speeds in Fluid Resistance: Utilizing the Reynolds Number

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  46. C

    Where can I learn all of this? Fluid Physics

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  47. P

    Loop of pumped fluid slowly falling into black hole.

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  48. L

    How Fast Can Water Flow from a Kitchen Faucet on the Third Floor?

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  49. F

    Fluid Mechanics HW How pressure in a tank affects exit velocity of a fluid

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  50. Egregious

    Simple question about fluid pressure (medical injection)

    Hello, and thank you kindly for considering my question. Background: Medical needles come in gauges such that a smaller gauge represents a larger needle. Scenario: Doctor Jack says "18 gauge needles are best for this procedure", but Doctor Jane says "27 gauge needles are best because...
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