Drawing lines with Gscript

tin3tin · 28th November 2010, 16:45

Here's a function for drawing lines with Gscript:

Code:

Loadplugin("GScript.dll")
blankclip(1,500,500,"RGB32", color=$FF0000FF)

# Example a line:
#DrawLine(canvas, 1,1,500,500, $FFFFFFFF)

#Example a red box:
#DrawLine(last,  100,100,400,100,5, $FFFF0000)
#DrawLine(last,  100,100,100,400,5, $FFFF0000) 
#DrawLine(last,  100,400,400,400,5, $FFFF0000) 
#DrawLine(last,  400,100,400,400,5, $FFFF0000) 

# Example a lot of lines:
GScript("""
for (i=0, 500,10){
DrawLine(last,  0,i,500,500-i,1, $FFFFFFFF)
DrawLine(last,  i,0,500-i,500,1, $FFFFFFFF)
}
    
""")

function DrawLine(clip canvas, val x0, val y0,val x1,val y1, val dsize, val dcolor)
{
    dtotal=canvas.framecount()
    OptCanvas=blankclip(1,canvas.width(),canvas.height(),"RGB32", color=$00000000)
    pen=blankclip(1,dsize,dsize,"RGB32", color=dcolor)
 
              dx = float(x1 - x0)
              dy = float(y1 - y0)
 
              sx = dx > 0 ? 1 : -1
              sy = dy > 0 ? 1 : -1
             
              dx = float(dx*sx)
              dy = float(dy*sy)         

              dxdy= float(dx/dy)
              dydx = float(dy/dx)          

              dxdy = dxdy *sx
              dydx = dydx *sy          

              py = float(y0)
              px = float(x0)
                
    GScript("""
              if( dx > dy )
              {
                
                 for(x=0, int(dx))
                 {
                    OptCanvas=Layer(OptCanvas,pen,"add",257,int(px),int(py))
                    px=px+sx
                    py=py+dydx
                 }
              }
              else
              {
                 for(y=0, int(dy))
                 {
                    OptCanvas=Layer(OptCanvas,pen,"add",257,int(px),int(py))
                    py=py+sy
                    px=px+dxdy
                 }
              }            
  
    """)
return Layer(Canvas,OptCanvas.loop(dtotal),"add",257,0,0)
}

tin3tin · 28th November 2010, 19:13

Tried to make a DrawCircle too, from this example: http://www.cs.unc.edu/~mcmillan/comp...e7/circle.html

However there is an error...

[Edit: Thanks Gavino! here's the working script:]

Code:

Loadplugin("GScript.dll")
blankclip(1,500,500,"RGB32", color=$FF0000FF)
            
DrawCircle(last, 250,250,100, 2, $FFFFFFFF)

function DrawCircle(clip canvas, val CenterX, val CenterY,val radius, val pensize, val pencolor)
{
    dtotal=canvas.framecount()
    OptCanvas=blankclip(1,canvas.width(),canvas.height(),"RGB32", color=$00000000)
    pen=blankclip(1,pensize,pensize,"RGB32", color=pencolor)            
    GScript("""   
        x = 0
        y = radius
        p = (5 - radius*4)/4

        while (x < y) 
        {
            x=x+1
            if (p < 0) {
                p = p+2*x+1
            } else {
                y=y-1
                p =p+ 2*(x-y+1)
            }
            OptCanvas=circlePoints(CenterX, CenterY, x, y, OptCanvas, pen)
            OptCanvas=Layer(OptCanvas,pen,"add",257,CenterX+int(x),CenterY+int(y))
        }       
""")

return Layer(Canvas,OptCanvas.loop(dtotal),"add",257,0,0)
}

function circlePoints(int cx, int cy, int x, int y, clip optCanvas, clip pen)
{

GScript("""       
        if (x == 0) {
            OptCanvas=Layer(OptCanvas,pen,"add",257, cx, cy + y)
            OptCanvas=Layer(OptCanvas,pen,"add",257, cx, cy - y)
            OptCanvas=Layer(OptCanvas,pen,"add",257, cx + y, cy)
            OptCanvas=Layer(OptCanvas,pen,"add",257, cx - y, cy)
        } else if (x == y) {
            OptCanvas=Layer(OptCanvas,pen,"add",257,cx + x, cy + y)
            OptCanvas=Layer(OptCanvas,pen,"add",257, cx - x, cy + y)
            OptCanvas=Layer(OptCanvas,pen,"add",257, cx + x, cy - y)
            OptCanvas=Layer(OptCanvas,pen,"add",257, cx - x, cy - y)
        } else if (x < y) {
            OptCanvas=Layer(OptCanvas,pen,"add",257, cx + x, cy + y)
            OptCanvas=Layer(OptCanvas,pen,"add",257, cx - x, cy + y)
            OptCanvas=Layer(OptCanvas,pen,"add",257, cx + x, cy - y)
            OptCanvas=Layer(OptCanvas,pen,"add",257, cx - x, cy - y)
            OptCanvas=Layer(OptCanvas,pen,"add",257, cx + y, cy + x)
            OptCanvas=Layer(OptCanvas,pen,"add",257, cx - y, cy + x)
            OptCanvas=Layer(OptCanvas,pen,"add",257, cx + y, cy - x)
            OptCanvas=Layer(OptCanvas,pen,"add",257, cx - y, cy - x)
        }
""")
            return OptCanvas
}

Gavino · 28th November 2010, 21:56

Code:

function DrawCircle( ... )
{
    ...
    optCanvas = circlePoints(CenterX, CenterY, x, y, OptCanvas, pen)
    ...
}

function circlePoints( ... )
{
        ...       
        if (x == 0) {
            ...
        } else if (x == y) {
            ...
}

tin3tin · 28th November 2010, 22:09

Thanks Gavino!

I was so close... and so blind...

Jenyok · 17th March 2013, 05:50

tin3tin
.
Exuse me, mate.
.
How to draw ARC ?
How to draw ELLIPSE ?
.
Gavino
.
Can you help, mate ?
.

tin3tin · 17th March 2013, 08:42

What I did was to google up some code handling the math and then changed it to Avisynth script.

StainlessS · 17th March 2013, 13:20

Maybe of interest:
http://en.wikipedia.org/wiki/Midpoint_circle_algorithm
http://en.wikipedia.org/wiki/Ellipse
http://en.wikipedia.org/wiki/Bresenh...line_algorithm
http://en.wikipedia.org/wiki/Digital...s_algorithm%29

Jenyok · 17th March 2013, 14:58

StainlessS
Thanks, mate.
.
.
I do not understand, why line of code does not works, see code below ?
.

Code:

LoadPlugin("C:\PROGRAM FILES\AVISYNTH 2.5\PLUGINS\GSCRIPT_11\gscript.dll")

function DrawCircle(clip canvas, val CenterX, val CenterY, val radius, val pensize, val pencolor)
{
  dtotal    = canvas.framecount()
  OptCanvas = blankclip(1, canvas.width(), canvas.height(), "RGB32", color=$00000000)
  pen       = blankclip(1, pensize, pensize, "RGB32", color=pencolor)            

  GScript("""
          x = 0
          y = radius
          p = (5 - radius * 4) / 4

          dt = 0

          while (x < y) {
            x = x + 1
            
            if (p < 0) {
              p = p + 2 * x + 1
            }
            else {
              y = y - 1
              p = p + 2 * (x - y + 1)
            }

            OptCanvas = circlePoints(CenterX, CenterY, x, y, OptCanvas, pen)
            OptCanvas = Layer(OptCanvas, pen, "add", 257, CenterX+int(x), CenterY+int(y))

            OptCanvas = SubTitle(OptCanvas, "p = "+string(p), x=5, y=5+dt, size=10, align=1, text_color=$FFFFFF, halo_color=$000000, font="Arial Cyr")   # Why does this line not works ?
            dt=dt+10
          }
  """)

  return (Layer(canvas, OptCanvas.loop(dtotal), "add", 257, 0, 0))
}


function circlePoints(int cx, int cy, int x, int y, clip optCanvas, clip pen)
{
  GScript("""       
          if (x == 0) {
            OptCanvas = Layer(OptCanvas, pen, "add", 257, cx, cy + y)
            OptCanvas = Layer(OptCanvas, pen, "add", 257, cx, cy - y)
            OptCanvas = Layer(OptCanvas, pen, "add", 257, cx + y, cy)
            OptCanvas = Layer(OptCanvas, pen, "add", 257, cx - y, cy)
          } 
          else if (x == y) {
            OptCanvas = Layer(OptCanvas, pen, "add", 257, cx + x, cy + y)
            OptCanvas = Layer(OptCanvas, pen, "add", 257, cx - x, cy + y)
            OptCanvas = Layer(OptCanvas, pen, "add", 257, cx + x, cy - y)
            OptCanvas = Layer(OptCanvas, pen, "add", 257, cx - x, cy - y)
          }
          else if (x < y) {
            OptCanvas = Layer(OptCanvas, pen, "add", 257, cx + x, cy + y)
            OptCanvas = Layer(OptCanvas, pen, "add", 257, cx - x, cy + y)
            OptCanvas = Layer(OptCanvas, pen, "add", 257, cx + x, cy - y)
            OptCanvas = Layer(OptCanvas, pen, "add", 257, cx - x, cy - y)
            OptCanvas = Layer(OptCanvas, pen, "add", 257, cx + y, cy + x)
            OptCanvas = Layer(OptCanvas, pen, "add", 257, cx - y, cy + x)
            OptCanvas = Layer(OptCanvas, pen, "add", 257, cx + y, cy - x)
            OptCanvas = Layer(OptCanvas, pen, "add", 257, cx - y, cy - x)
          }
  """)

  return (OptCanvas)
}



BlankClip(length=50, width=768, height=576, fps=25.0, channels=2, color=$000000)

x2 = Width() / 2
y2 = Height() / 2

DrawCircle(last, x2+200, y2, 100, 2, $FFFFFFFF)

ConvertToYUY2()

Gavino · 17th March 2013, 21:07

Quote:

Originally Posted by Jenyok

I do not understand, why line of code does not works, see code below ?

It's because OptCanvas is created transparent (alpha=0), and Subtitle() does not change the alpha layer.
You need to add this line after the Subtitle call:

Code:

OptCanvas = OptCanvas.Mask(OptCanvas.ShowAlpha().SubTitle("p = "+string(p), x=5, y=5+dt, size=10, align=1, text_color=$FFFFFF, halo_color=$FFFFFF, font="Arial Cyr"))

This will set alpha to 255 (opaque) where Subtitle() has written the text.

Jenyok · 18th March 2013, 06:34

Gavino
.
Thanks, mate.
It works.
.

28th November 2010, 21:56	#3 \| Link
Gavino Avisynth language lover Join Date: Dec 2007 Location: Spain Posts: 3,442	Code: function DrawCircle( ... ) { ... optCanvas = circlePoints(CenterX, CenterY, x, y, OptCanvas, pen) ... } function circlePoints( ... ) { ... if (x == 0) { ... } else if (x == y) { ... } __________________ GScript and GRunT - complex Avisynth scripting made easier

28th November 2010, 22:09	#4 \| Link
tin3tin Registered User Join Date: Mar 2005 Posts: 366	Thanks Gavino! I was so close... and so blind... __________________ DVD slideshow GUI(Freeware).

17th March 2013, 05:50	#5 \| Link
Jenyok Warm and fuzzy Join Date: Apr 2010 Location: Moscow, Russia Posts: 206	tin3tin . Exuse me, mate. . How to draw ARC ? How to draw ELLIPSE ? . Gavino . Can you help, mate ? . __________________ Warm and fuzzy (white and fluffy) Last edited by Jenyok; 17th March 2013 at 06:03.

17th March 2013, 08:42	#6 \| Link
tin3tin Registered User Join Date: Mar 2005 Posts: 366	What I did was to google up some code handling the math and then changed it to Avisynth script. __________________ DVD slideshow GUI(Freeware).

17th March 2013, 13:20	#7 \| Link
StainlessS HeartlessS Usurer Join Date: Dec 2009 Location: Over the rainbow Posts: 11,406	Maybe of interest: http://en.wikipedia.org/wiki/Midpoint_circle_algorithm http://en.wikipedia.org/wiki/Ellipse http://en.wikipedia.org/wiki/Bresenh...line_algorithm http://en.wikipedia.org/wiki/Digital...s_algorithm%29 __________________ I sometimes post sober. StainlessS@MediaFire ::: AND/OR ::: StainlessS@SendSpace "Some infinities are bigger than other infinities", but how many of them are infinitely bigger ???

18th March 2013, 06:34	#10 \| Link
Jenyok Warm and fuzzy Join Date: Apr 2010 Location: Moscow, Russia Posts: 206	Gavino . Thanks, mate. It works. . __________________ Warm and fuzzy (white and fluffy)

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