nap-time commit

2026-05-05 14:23:20 +02:00
parent 6747f0e243
commit 95a8502d0f
6 changed files with 61 additions and 81 deletions
--- a/docs/usage.md
+++ b/docs/usage.md
@@ -5,7 +5,8 @@ The genplotting library use, as a backend, an external
 who can be installed with the [libtthimage](https://git.tetalab.org/tTh/libtthimage) and convert scratchfiles to
 [Targa](https://en.wikipedia.org/wiki/Truevision_TGA) image file. 

-Three steps : initialize, use and terminating.
+For drawing an *useless graphic*, you have to follow three steps:
+initialize, use and terminating.

 ## Initialize

--- a/exemples.md
+++ b/exemples.md
@@ -1,24 +0,0 @@
-# Genplotting exemples
-
-## Spiral
-
-Code source : [spirale.f90](spirale.f90) / if you change the parameter
-in the call to `do_spirale`, you can see some nice variations on the
-spiraling thing.
-
-![#UselessGraphic : la spirale](picz/spirale.png)
-
-This was my first testbed for this new *disruptive* technology, but
-there was so many variations of spirales, and i'm thinking about
-a powerfull spiral generator. *Stay tuned, film at 11*.
-
-## Dessins numériques
-
-By the way, I'm using all that *futilo-technology* for trying to
-make some
-[numeric pictures](http://maison.tth.netlib.re/dessins/numerique.html)
-(aka #UselessGraphic). I try to use various mathematic fundations, and
-I hack and divert and modify and ignore all that for just make
-[UselessGraphic](https://mastodon.tetaneutral.net/tags/uselessgraphic).
-*Feel free to share and enjoy*.
-
--- a/genplotting.f90
+++ b/genplotting.f90
@@ -11,16 +11,25 @@ module genplotting
  real      ::    xoffset, yoffset, xscale, yscale
  private   ::    xoffset, yoffset, xscale, yscale

-  integer   ::    outunit
+  real      ::    rotation
+  private   ::    rotation
+
+  integer   ::    outunit = 6
  private   ::    outunit

 contains
 ! ---------------------------------------------------------
+! the first parameter _must_ be 0.
+! the second can be
+!    - the name of a file for recoding plot instructions
+!  or
+!    - an empty string for send plot command to stdout
+!
 subroutine genp_init (foo, fname)
  integer, intent(in)             :: foo
  character (len=*), intent(in)   :: fname

-  if (FOO .NE. 0)   THEN
+  IF (FOO .NE. 0)   THEN
    WRITE(0, '("FOO .NE. 0")')
    CALL EXIT(1) 
  END IF
@@ -35,6 +44,8 @@ subroutine genp_init (foo, fname)
  ymin = 9e9       ;       ymax = -9e9
  xoffset = 0.0    ;       yoffset = 0.0
  xscale  = 0.0    ;       yscale  = 0.0
+  rotation = 0.0
+
 end subroutine
 ! ---------------------------------------------------------
 subroutine genp_set_offset(ox, oy)
@@ -76,6 +87,14 @@ subroutine genp_line(xa, ya, xb, yb, color)
  call genp_draw(xb, yb, color)
 end subroutine
 ! ---------------------------------------------------------
+subroutine plot_axes(amp)
+  real, intent(in)     :: amp
+  call genp_move(0.0, -amp)
+  call genp_draw(0.0,  amp, 7)
+  call genp_move(-amp, 0.0)
+  call genp_draw( amp, 0.0, 7)
+end subroutine
+! ---------------------------------------------------------
 subroutine genp_end (foo)
  integer, intent(in)    :: foo

--- a/oscilloscope.f90
+++ b/oscilloscope.f90
@@ -1,3 +1,9 @@
+!
+!                    OSCILLOSCOPE EXPERIMENT
+!
+! this crapware is released by tTh under the
+!             DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
+!
 program oscilloscope
  use genplotting
  implicit none
@@ -8,40 +14,41 @@ program oscilloscope
  call srand(time())
  call genp_init (0, 'WS/oscilloscope.scratch')

-  frequences(1) = 0.86
-  frequences(2) = 1.77
-  frequences(3) = 1.56
-  frequences(4) = 3.04
+  frequences(1) = 24.86
+  frequences(2) = 29.77
+  frequences(3) = 37.56
+  frequences(4) = 49.3
+
+  call do_oscilloscope(frequences, 2)

-  call do_oscilloscope(frequences, 1)
  call genp_end (0)
 contains
 ! ---------------------------------------------------------
-subroutine plot_axes(amp)
-  real, intent(in)     :: amp
-  call genp_move(0.0, -amp)
-  call genp_draw(0.0,  amp, 7)
-  call genp_move(-amp, 0.0)
-  call genp_draw( amp, 0.0, 7)
-end subroutine
+real function compute_a_value(clk, freq, phase)
+  real, intent(in)    :: clk, freq, phase
+  real                :: v, f
+  f = freq*(clk+phase)
+  v = sin(f) + (0.3 * sin(3*f)) + (0.1 * sin(5*f))
+  compute_a_value = v
+end function
 ! ---------------------------------------------------------
-subroutine plot_a_trace(freq, phy, nbsteps, ypos)
+subroutine plot_a_trace(freq, phy, nbsteps, ypos, col)
  real, intent(in)        :: freq, phy, ypos
-  integer, intent(in)     :: nbsteps
+  integer, intent(in)     :: nbsteps, col

  integer          idx
  real             rstep, px, py
  logical          firstdot

-  firstdot = .true.
+  firstdot = .TRUE.
  do idx=0, nbsteps
    rstep = (real(idx)/real(nbsteps)) 
    px    = -10.0 + (20.0 * rstep)
-    py    = ypos + sin(15*(rstep+phy)*freq) 
+    py = ypos + compute_a_value (rstep, freq, phy)
    if (firstdot) then
      call genp_move(px, py)   ;   firstdot = .false.
    else
-      call genp_draw(px, py, 2)
+      call genp_draw(px, py, col)
    endif
  enddo

@@ -51,10 +58,10 @@ subroutine do_oscilloscope(freqs, col)
  real, intent(in), dimension(4)   :: freqs
  integer, intent(in)              :: col

-  call plot_a_trace(freqs(1), 0.2, 90,  6.66)
-  call plot_a_trace(freqs(2), 1.0, 90,  3.33)
-  call plot_a_trace(freqs(3), 2.6, 90, -3.33)
-  call plot_a_trace(freqs(4), 3.9, 90, -6.66)
+  call plot_a_trace(freqs(1), 0.2, 120,  6.66, col)
+  call plot_a_trace(freqs(2), 1.0, 120,  3.33, col)
+  call plot_a_trace(freqs(3), 2.6, 120, -3.33, col)
+  call plot_a_trace(freqs(4), 3.1, 120, -6.66, col)
  call plot_axes(10.0)

 end subroutine
--- a/starfield.f90
+++ b/starfield.f90
@@ -1,24 +1,30 @@
 !
 !         BUILD A STAR FIELD
+
+! this crapware is released by tTh under the
+!             DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
 !
 program starfield
  use genplotting
  implicit none
  write (0, '(A)') "----[ genplotting starfield ]----"
  call genp_init (0, 'WS/starfield.scratch')
-  call do_starfield (451)
+  call do_starfield (200)
  call genp_end (0)
 contains
 ! ---------------------------------------------------------
 subroutine plot_a_star(at_x, at_y, sz, color)
  real, intent(in)        :: at_x, at_y, sz
  integer, intent(in)     :: color
+
  integer                 :: idx
  real                    :: rad, xv, yv
+
  write(0, '("plot a star ", 2F8.3)') at_x, at_y
  call genp_set_offset(at_x, at_y)
  do idx=0, 360, 36
-    rad = 0.042 + (real(idx) * (3.14159 / 180))
+    !   convert index to radians
+    rad = real(idx) * (3.14159 / 180)
    xv = sz * sin(rad)    ;    yv = sz * cos(rad)
    call genp_move(0.0, 0.0)
    call genp_draw(xv, yv, color)
@@ -27,12 +33,13 @@ end subroutine
 ! ---------------------------------------------------------
 subroutine do_starfield (nbstar)
  integer, intent(in)     :: nbstar
+
  integer         idx, color
  real            px, py, sz
  do idx=1, nbstar
    px = (rand(0) * 10.00) - 5.00
    py = (rand(0) * 10.00) - 5.00
-    sz = (rand(0) *  0.16) + 0.16
+    sz = (rand(0) *  0.30) + 0.12
    color = 1 + mod(idx, 7)
    call plot_a_star(px, py, sz, color)
  end do
--- a/usage.md
+++ b/usage.md
@@ -1,30 +0,0 @@
-# Usage
-
-The genplotting library use, as a backend, an external 
-[software](https://git.tetalab.org/tTh/libtthimage/src/branch/master/Tools/genplot2.c)
-who can be installed with the [libtthimage](https://git.tetalab.org/tTh/libtthimage) and convert scratchfiles to
-[Targa](https://en.wikipedia.org/wiki/Truevision_TGA) image file. 
-
-Three steps : initialize, use and terminating.
-
-## Initialize
-
-Call the subroutine `genp_init` with two parameters.
-The first is an integer and must be 0. 
-The second is the filename for recording the plottings instructions,
-if this filename is an empty string, *stdout* will be used.
-
-## Use it
-
- real xa, ya, xb, yb
- integer color
- call genp_move(xa, ya)
- call genp_draw(xa, ya, color)
- call genp_line(xa, ya, xb, yb, color)
-
-## Terminator
-
- call genp_end(0)
-
-
-