testing recent changes

genplotting.f90

@@ -57,10 +57,21 @@ subroutine genp_get_offset(ox, oy)
   ox = xoffset      ;      oy = yoffset
 end subroutine
 ! ---------------------------------------------------------
+! new Tue May 12 06:51:57 PM UTC 2026
+subroutine genp_set_scale(sx, sy)
+  real, intent(in)     :: sx, sy
+  xscale = sx      ;      yscale = sy
+end subroutine
+subroutine genp_get_scale(sx, sy)
+  real, intent(out)     :: sx, sy
+  sx = xscale      ;      sy = yscale
+end subroutine
+! ---------------------------------------------------------
 subroutine genp_move (px, py)
   real, intent(in)        :: px, py
   real                    :: lx, ly
-  lx = px + xoffset     ;     ly = py + yoffset
+  lx = (px*xscale) + xoffset
+  ly = (py*yscale) + yoffset
   write (outunit, '(2F12.5, I5)') lx, ly, -1
   if (lx .lt. xmin)      xmin = lx
   if (lx .gt. xmax)      xmax = lx
@@ -72,7 +83,8 @@ subroutine genp_draw (px, py, color)
   real, intent(in)        :: px, py
   integer, intent(in)     :: color
   real                    :: lx, ly
-  lx = px + xoffset     ;     ly = py + yoffset
+  lx = (px*xscale) + xoffset
+  ly = (py*yscale) + yoffset
   write (outunit, '(2F12.5, I5)') lx, ly, color
   if (lx .lt. xmin)      xmin = lx
   if (lx .gt. xmax)      xmax = lx
@@ -95,6 +107,34 @@ subroutine genp_plot_axes(amp)
   call genp_draw( amp, 0.0, 7)
 end subroutine
 ! ---------------------------------------------------------
+subroutine genp_circle(radius, steps, color)
+  real, intent(in)      :: radius
+  integer, intent(in)   :: steps, color
+
+  integer               :: idx
+  real                  :: fk, ang, x, y
+  logical               :: firstdot
+
+  if (steps .LT.3 ) then
+    write(0, '("circle: steps ", I3, " bad value")') steps
+    return
+  endif
+
+  firstdot = .TRUE.
+  do idx=0, steps
+    fk = real(idx) / real(steps)
+    ang = 6.283185307 * fk
+    ! write(0, '(I5, "  ->  ", 2F10.5)') idx, fk, ang
+    x = radius * cos(ang)   ;   y = radius * sin(ang)
+    if (firstdot) then
+      call genp_move(x, y)   ;    firstdot = .FALSE.
+    else
+      call genp_draw(x, y, color)
+    endif
+  enddo
+
+end subroutine
+! ---------------------------------------------------------
 subroutine genp_end (foo)
   integer, intent(in)    :: foo
 

testbed.f90

@@ -2,8 +2,21 @@ program testbed
   use genplotting
   implicit none
 
+  integer     idx
+  real        fdx, xp, yp, scx, scy
+
   call genp_init(0, "foo.scratch")
-  call genp_plot_axes(13.37)
+  scx = 0.8   ;   scy = 1.5
+  do idx=5, 60
+    fdx = real(idx)
+    xp = 3.5 * cos((fdx/14.0)-0.7)
+    yp = 3.5 * sin((fdx/10.0)+0.3)
+    call genp_set_offset(xp, yp)
+    call genp_set_scale(scx, scy)
+    call genp_circle(fdx, 60, 1+mod(idx, 3))
+    scx = scx + 0.0075
+    scy = scy - 0.0075
+  enddo
   call genp_end(0)
   call genp_do_render("foo.scratch", "foo.tga", 512, 512)