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Showing posts with the label Computer Graphics

Bresenham’s Line Algorithm

Bresenham’s Line Algorithm
Bresenham’s Line Algorithm: The Bresanhan’s Line Algorithm is one of the scan line algoirthm. The big advantege of Bresanham’s line Algorithm is that it is use only integer calculation.
Algorithm :
step1 : input two end point of line,showing the left end point A(X0 , Y0) and B(X1 , Y1)
step2 : plot the point (X0 , Y0)
Step3 : Calculate dx , dy, 2dx , 2dy and 2dx – 2dy
dx = X1 -X0 dy = Y1 – Y0 2dx = 2( x1 -x0 ) 2dy = 2( Y1 – Y0 )
Po = 2dy – dx
step 4 : taking k= 0 ; if (Pk <0 ) then next point is ( Xk+i , y1) ; and Pk+1 = Pk + 2dy ;
else point is (Xk , Yk+i) Pk+1 = pk + 2(dx – dy )

step5 : Repeat step 4 (dx -1) times

Digital differential analyzer( DDA Algorithm)

DDA ALGORITHM
DDA Algorithm: DDA Algorithm stand for Digital Differential Analyzer Algorithm. DDA Algorithm is the simple line generation algorithm. Let’s what is DDA algorithm on simple way
Algorithm:
Step1 : Get Input of two end point A(X0 , Y0) and B(X1 , Y1)
Step2 : Calculate the Difference Between two point dx and dy dx = X1 – X0 dy = Y1 – Y0
step 3 : if dx > dy , then you need move step in X Coordinate, otherwise in Y coordinate
if ( dx>dy)     step=dx ;
else     step = dy ;
step4 : Calculate the increment X and Y coordinate
Xinc = dx / step ; Yinc = dy / step ;
step5 : put the X coordinate and Y coordinate accordingly
for ( int v = 0 ; v< step; v++) X= X+ Xinc ; Y = Y + Yinc; put Pix (Round(x), Round(y)); }
Advantage Of DDA Algorithm
1) it is simplest algorithm 2) it does not require special skills for implementation 3) It is a faster method for calculating pixel positions
Disadvantage of DDA Algori…