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Bitmap/Bézier curves/Quadratic: Difference between revisions
Added solution for MATLAB
(Added BBC BASIC) |
(Added solution for MATLAB) |
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Graphics[{BSplineCurve[pts], Green, Line[pts], Red, Point[pts]}]</lang>
[[File:MmaQuadraticBezier.png]]
=={{header|MATLAB}}==
Note: Store this function in a file named "bezierQuad.mat" in the @Bitmap folder for the Bitmap class defined [[Bitmap#MATLAB|here]].
<lang MATLAB>
function bezierQuad(obj,pixel_0,pixel_1,pixel_2,color,varargin)
if( isempty(varargin) )
resolution = 20;
else
resolution = varargin{1};
end
%Calculate time axis
time = (0:1/resolution:1)';
timeMinus = 1-time;
%The formula for the curve is expanded for clarity, the lack of
%loops is because its calculation has been vectorized
curve = (timeMinus.^2)*pixel_0; %First term of polynomial
curve = curve + (2.*time.*timeMinus)*pixel_1; %second term of polynomial
curve = curve + (time.^2)*pixel_2; %third term of polynomial
curve = round(curve); %round each of the points to the nearest integer
%connect each of the points in the curve with a line using the
%Bresenham Line algorithm
for i = (1:length(curve)-1)
obj.bresenhamLine(curve(i,:),curve(i+1,:),color);
end
assignin('caller',inputname(1),obj); %saves the changes to the object
end
</lang>
Sample usage:
This will generate the image example for the Go solution.
<lang MATLAB>
>> img = Bitmap(400,300);
>> img.fill([223 255 239]);
>> img.bezierQuad([20 150],[500 -100],[300 280],[63 143 239],21);
>> disp(img)
</lang>
=={{header|OCaml}}==
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