Drawing an ellipse

[PhilOfPerth]

Code: (Select All)

{{CodeStart}}

{{Cl|Screen}} {{Cl|_NewImage}}({{Text|800|#F580B1}}, {{Text|600|#F580B1}}, {{Text|32|#F580B1}})



{{Cl|Dim}} TransRed {{Cl|As}} {{Cl|_Unsigned}} {{Cl|Long}}

{{Cl|Dim}} TransGreen {{Cl|As}} {{Cl|_Unsigned}} {{Cl|Long}}

{{Cl|Dim}} TransBlue {{Cl|As}} {{Cl|_Unsigned}} {{Cl|Long}}

TransRed = {{Cl|_RGBA}}({{Text|255|#F580B1}}, {{Text|0|#F580B1}}, {{Text|0|#F580B1}}, {{Text|128|#F580B1}})

TransGreen = {{Cl|_RGBA}}({{Text|0|#F580B1}}, {{Text|255|#F580B1}}, {{Text|0|#F580B1}}, {{Text|128|#F580B1}})

TransBlue = {{Cl|_RGBA}}({{Text|0|#F580B1}}, {{Text|0|#F580B1}}, {{Text|255|#F580B1}}, {{Text|128|#F580B1}})



{{Cl|Call}} {{Text|CircleFill|#55FF55}}({{Text|100|#F580B1}}, {{Text|100|#F580B1}}, {{Text|75|#F580B1}}, TransRed)

{{Cl|Call}} {{Text|CircleFill|#55FF55}}({{Text|120|#F580B1}}, {{Text|120|#F580B1}}, {{Text|75|#F580B1}}, TransBlue)



{{Cl|Call}} {{Text|EllipseFill|#55FF55}}({{Text|550|#F580B1}}, {{Text|100|#F580B1}}, {{Text|150|#F580B1}}, {{Text|75|#F580B1}}, TransBlue)

{{Cl|Call}} {{Text|EllipseFill|#55FF55}}({{Text|570|#F580B1}}, {{Text|120|#F580B1}}, {{Text|150|#F580B1}}, {{Text|75|#F580B1}}, TransGreen)



{{Cl|Call}} {{Text|EllipseTilt|#55FF55}}({{Text|200|#F580B1}}, {{Text|400|#F580B1}}, {{Text|150|#F580B1}}, {{Text|75|#F580B1}}, {{Text|0|#F580B1}}, TransGreen)

{{Cl|Call}} {{Text|EllipseTilt|#55FF55}}({{Text|220|#F580B1}}, {{Text|420|#F580B1}}, {{Text|150|#F580B1}}, {{Text|75|#F580B1}}, {{Text|3.14|#F580B1}} / {{Text|4|#F580B1}}, TransRed)



{{Cl|Call}} {{Text|EllipseTiltFill|#55FF55}}({{Text|0|#F580B1}}, {{Text|550|#F580B1}}, {{Text|400|#F580B1}}, {{Text|150|#F580B1}}, {{Text|75|#F580B1}}, {{Text|3.14|#F580B1}} / {{Text|6|#F580B1}}, TransRed)

{{Cl|Call}} {{Text|EllipseTiltFill|#55FF55}}({{Text|0|#F580B1}}, {{Text|570|#F580B1}}, {{Text|420|#F580B1}}, {{Text|150|#F580B1}}, {{Text|75|#F580B1}}, {{Text|3.14|#F580B1}} / {{Text|4|#F580B1}}, TransGreen)



{{Cl|End}}



{{Cl|Sub}} {{Text|CircleFill|#55FF55}} (CX {{Cl|As}} {{Cl|Integer}}, CY {{Cl|As}} {{Cl|Integer}}, R {{Cl|As}} {{Cl|Integer}}, C {{Cl|As}} {{Cl|_Unsigned}} {{Cl|Long}})

    {{Text|<nowiki>' CX = center x coordinate</nowiki>|#919191}}

    {{Text|<nowiki>' CY = center y coordinate</nowiki>|#919191}}

    {{Text|<nowiki>'  R = radius</nowiki>|#919191}}

    {{Text|<nowiki>'  C = fill color</nowiki>|#919191}}

    {{Cl|Dim}} Radius {{Cl|As}} {{Cl|Integer}}, RadiusError {{Cl|As}} {{Cl|Integer}}

    {{Cl|Dim}} X {{Cl|As}} {{Cl|Integer}}, Y {{Cl|As}} {{Cl|Integer}}

    Radius = {{Cl|Abs}}(R)

    RadiusError = -Radius

    X = Radius

    Y = {{Text|0|#F580B1}}

    {{Cl|If}} Radius = {{Text|0|#F580B1}} {{Cl|Then}} {{Cl|PSet}} (CX, CY), C: {{Cl|Exit Sub}}

    {{Cl|Line}} (CX - X, CY)-(CX + X, CY), C, BF

    {{Cl|While}} X > Y

        RadiusError = RadiusError + Y * {{Text|2|#F580B1}} + {{Text|1|#F580B1}}

        {{Cl|If}} RadiusError >= {{Text|0|#F580B1}} {{Cl|Then}}

            {{Cl|If}} X <> Y + {{Text|1|#F580B1}} {{Cl|Then}}

                {{Cl|Line}} (CX - Y, CY - X)-(CX + Y, CY - X), C, BF

                {{Cl|Line}} (CX - Y, CY + X)-(CX + Y, CY + X), C, BF

            {{Cl|End If}}

            X = X - {{Text|1|#F580B1}}

            RadiusError = RadiusError - X * {{Text|2|#F580B1}}

        {{Cl|End If}}

        Y = Y + {{Text|1|#F580B1}}

        {{Cl|Line}} (CX - X, CY - Y)-(CX + X, CY - Y), C, BF

        {{Cl|Line}} (CX - X, CY + Y)-(CX + X, CY + Y), C, BF

    {{Cl|Wend}}

{{Cl|End Sub}}



{{Cl|Sub}} {{Text|EllipseFill|#55FF55}} (CX {{Cl|As}} {{Cl|Integer}}, CY {{Cl|As}} {{Cl|Integer}}, a {{Cl|As}} {{Cl|Integer}}, b {{Cl|As}} {{Cl|Integer}}, C {{Cl|As}} {{Cl|_Unsigned}} {{Cl|Long}})

    {{Text|<nowiki>' CX = center x coordinate</nowiki>|#919191}}

    {{Text|<nowiki>' CY = center y coordinate</nowiki>|#919191}}

    {{Text|<nowiki>'  a = semimajor axis</nowiki>|#919191}}

    {{Text|<nowiki>'  b = semiminor axis</nowiki>|#919191}}

    {{Text|<nowiki>'  C = fill color</nowiki>|#919191}}

    {{Cl|If}} a = {{Text|0|#F580B1}} {{Cl|OR (boolean)|Or}} b = {{Text|0|#F580B1}} {{Cl|Then}} {{Cl|Exit Sub}}

    {{Cl|Dim}} h2 {{Cl|As}} {{Cl|_Integer64}}

    {{Cl|Dim}} w2 {{Cl|As}} {{Cl|_Integer64}}

    {{Cl|Dim}} h2w2 {{Cl|As}} {{Cl|_Integer64}}

    {{Cl|Dim}} x {{Cl|As}} {{Cl|Integer}}

    {{Cl|Dim}} y {{Cl|As}} {{Cl|Integer}}

    w2 = a * a

    h2 = b * b

    h2w2 = h2 * w2

    {{Cl|Line}} (CX - a, CY)-(CX + a, CY), C, BF

    {{Cl|DO...LOOP|Do While}} y < b

        y = y + {{Text|1|#F580B1}}

        x = {{Cl|Sqr}}((h2w2 - y * y * w2) \ h2)

        {{Cl|Line}} (CX - x, CY + y)-(CX + x, CY + y), C, BF

        {{Cl|Line}} (CX - x, CY - y)-(CX + x, CY - y), C, BF

    {{Cl|Loop}}

{{Cl|End Sub}}



{{Cl|Sub}} {{Text|EllipseTilt|#55FF55}} (CX, CY, a, b, ang, C {{Cl|As}} {{Cl|_Unsigned}} {{Cl|Long}})

    {{Text|<nowiki>'  CX = center x coordinate</nowiki>|#919191}}

    {{Text|<nowiki>'  CY = center y coordinate</nowiki>|#919191}}

    {{Text|<nowiki>'  a = semimajor axis</nowiki>|#919191}}

    {{Text|<nowiki>'  b = semiminor axis</nowiki>|#919191}}

    {{Text|<nowiki>' ang = clockwise orientation of semimajor axis in radians (0 default)</nowiki>|#919191}}

    {{Text|<nowiki>'  C = fill color</nowiki>|#919191}}

    {{Cl|For}} k = {{Text|0|#F580B1}} {{Cl|To}} {{Text|6.283185307179586|#F580B1}} + {{Text|.025|#F580B1}} {{Cl|Step}} {{Text|.025|#F580B1}}

        i = a * {{Cl|Cos}}(k) * {{Cl|Cos}}(ang) + b * {{Cl|Sin}}(k) * {{Cl|Sin}}(ang)

        j = -a * {{Cl|Cos}}(k) * {{Cl|Sin}}(ang) + b * {{Cl|Sin}}(k) * {{Cl|Cos}}(ang)

        i = i + CX

        j = -j + CY

        {{Cl|If}} k <> {{Text|0|#F580B1}} {{Cl|Then}}

            {{Cl|Line}} -(i, j), C

        {{Cl|Else}}

            {{Cl|PSet}} (i, j), C

        {{Cl|End If}}

    {{Cl|Next}}

{{Cl|End Sub}}



{{Cl|Sub}} {{Text|EllipseTiltFill|#55FF55}} (destHandle&, CX, CY, a, b, ang, C {{Cl|As}} {{Cl|_Unsigned}} {{Cl|Long}})

    {{Text|<nowiki>'  destHandle& = destination handle</nowiki>|#919191}}

    {{Text|<nowiki>'  CX = center x coordinate</nowiki>|#919191}}

    {{Text|<nowiki>'  CY = center y coordinate</nowiki>|#919191}}

    {{Text|<nowiki>'  a = semimajor axis</nowiki>|#919191}}

    {{Text|<nowiki>'  b = semiminor axis</nowiki>|#919191}}

    {{Text|<nowiki>' ang = clockwise orientation of semimajor axis in radians (0 default)</nowiki>|#919191}}

    {{Text|<nowiki>'  C = fill color</nowiki>|#919191}}

    {{Cl|Dim}} max {{Cl|As}} {{Cl|Integer}}, mx2 {{Cl|As}} {{Cl|Integer}}, i {{Cl|As}} {{Cl|Integer}}, j {{Cl|As}} {{Cl|Integer}}

    {{Cl|Dim}} prc {{Cl|As}} {{Cl|_Unsigned}} {{Cl|Long}}

    {{Cl|Dim}} D {{Cl|As}} {{Cl|Integer}}, S {{Cl|As}} {{Cl|Integer}}

    D = {{Cl|_DEST (function)|_Dest}}: S = {{Cl|_SOURCE (function)|_Source}}

    prc = {{Cl|_RGB32}}({{Text|255|#F580B1}}, {{Text|255|#F580B1}}, {{Text|255|#F580B1}}, {{Text|255|#F580B1}})

    {{Cl|If}} a > b {{Cl|Then}} max = a + {{Text|1|#F580B1}} {{Cl|Else}} max = b + {{Text|1|#F580B1}}

    mx2 = max + max

    tef& = {{Cl|_NewImage}}(mx2, mx2)

    {{Cl|_Dest}} tef&

    {{Cl|_Source}} tef&

    {{Cl|For}} k = {{Text|0|#F580B1}} {{Cl|To}} {{Text|6.283185307179586|#F580B1}} + {{Text|.025|#F580B1}} {{Cl|Step}} {{Text|.025|#F580B1}}

        i = max + a * {{Cl|Cos}}(k) * {{Cl|Cos}}(ang) + b * {{Cl|Sin}}(k) * {{Cl|Sin}}(ang)

        j = max + a * {{Cl|Cos}}(k) * {{Cl|Sin}}(ang) - b * {{Cl|Sin}}(k) * {{Cl|Cos}}(ang)

        {{Cl|If}} k <> {{Text|0|#F580B1}} {{Cl|Then}}

            {{Cl|Line}} (lasti, lastj)-(i, j), prc

        {{Cl|Else}}

            {{Cl|PSet}} (i, j), prc

        {{Cl|End If}}

        lasti = i: lastj = j

    {{Cl|Next}}

    {{Cl|Dim}} xleft(mx2) {{Cl|As}} {{Cl|Integer}}, xright(mx2) {{Cl|As}} {{Cl|Integer}}, x {{Cl|As}} {{Cl|Integer}}, y {{Cl|As}} {{Cl|Integer}}

    {{Cl|For}} y = {{Text|0|#F580B1}} {{Cl|To}} mx2

        x = {{Text|0|#F580B1}}

        {{Cl|While}} {{Cl|Point}}(x, y) <> prc {{Cl|AND (boolean)|And}} x < mx2

            x = x + {{Text|1|#F580B1}}

        {{Cl|Wend}}

        xleft(y) = x

        {{Cl|While}} {{Cl|Point}}(x, y) = prc {{Cl|AND (boolean)|And}} x < mx2

            x = x + {{Text|1|#F580B1}}

        {{Cl|Wend}}

        {{Cl|While}} {{Cl|Point}}(x, y) <> prc {{Cl|AND (boolean)|And}} x < mx2

            x = x + {{Text|1|#F580B1}}

        {{Cl|Wend}}

        {{Cl|If}} x = mx2 {{Cl|Then}} xright(y) = xleft(y) {{Cl|Else}} xright(y) = x

    {{Cl|Next}}

    {{Cl|_Dest}} destHandle&

    {{Cl|For}} y = {{Text|0|#F580B1}} {{Cl|To}} mx2

        {{Cl|If}} xleft(y) <> mx2 {{Cl|Then}} {{Cl|Line}} (xleft(y) + CX - max, y + CY - max)-(xright(y) + CX - max, y + CY - max), C, BF

    {{Cl|Next}}

    {{Cl|_Dest}} D: {{Cl|_Dest}} S

    {{Cl|_FreeImage}} tef&

{{Cl|End Sub}}

{{CodeEnd}}

Those are the routines we worked up ages ago for Circles and Ellipses.  They should handle whatever you need for them too, and they've been optimized for speed with QB64PE. 

Thank you Steve. But OldMoses has given me what I needed (see previous post) 

I cleaned that mess up. If you look above your post, you can see the example and routines which I was trying to post instead.  That gobbledygook isn't going to be of use to you, or anyone else. 

Wow!
 Thanks Steve; It's shown me some of the incredible things that can be done with this language.