EllipseFill

[bplus]

Hi Steve,

The New Circle method is failing the alpha test with 1 overlapping line in upper and lower halves and it is being edged out by the old circle method in the long loop time test.

Amazingly the Ellipse Fill method is edging out the old gold standard circle fill method and still passing the alpha test.

Here is my test code, comment and uncomment as needed in method block and time report line:

Code: QB64: [Select]

1. DEFINT A-Z
2. SCREEN _NEWIMAGE(1220, 620, 32)
3. _SCREENMOVE 100, 20
4. _DELAY 1
5. FOR i = 0 TO 1000
6.     t = t + i
7. NEXT
8. 'who goes first might be disadvantage in time
9.  
10. 'comment out the one not being tested against the old circle method
11. 'start## = TIMER
12. 'CIRCLE (915, 305), 300, _RGBA32(100, 100, 100, 100), , , 1
13. 'NewCircleFill 915, 305, 300, _RGBA32(0, 100, 0, 100)
14. 'FOR i = 1 TO 10000
15. '    NewCircleFill 915, 305, 300, _RGBA32(0, 100, 0, 100)
16. 'NEXT
17. 'NewCircleTime## = TIMER - start##
18.  
19. start## = TIMER
20. CIRCLE (915, 305), 300, _RGBA32(100, 100, 100, 100), , , 1
21. EllipseFill 915, 305, 300, 300, _RGBA32(0, 100, 0, 100)
22. FOR i = 1 TO 10000
23.     EllipseFill 915, 305, 300, 300, _RGBA32(0, 100, 0, 100)
24. NEXT
25. EllipseTime## = TIMER - start##
26.  
27. ' ==================================================== compare to the old gold standard
28. start## = TIMER
29. CIRCLE (305, 305), 300, _RGBA32(100, 100, 100, 100), , , 1
30. CircleFill 305, 305, 300, _RGBA32(0, 100, 0, 100)
31. FOR i = 1 TO 10000
32.     CircleFill 305, 305, 300, _RGBA32(0, 100, 0, 100)
33. NEXT
34. OldCircleTime## = TIMER - start##
35.  
36. 'Comment out one of next 2 below
37.  
38. 'PRINT "Old circle time:"; OldCircleTime##; ", New circle time:"; NewCircleTime##
39.  
40. PRINT "Old circle time:"; OldCircleTime##; ", Ellipse fill time:"; EllipseTime##
41.  
42.  
43. 'old circle fill
44. SUB CircleFill (CX AS INTEGER, CY AS INTEGER, R AS INTEGER, C AS _UNSIGNED LONG)
45.     DIM Radius AS INTEGER, RadiusError AS INTEGER
46.     DIM X AS INTEGER, Y AS INTEGER
47.  
48.     Radius = ABS(R)
49.     RadiusError = -Radius
50.     X = Radius
51.     Y = 0
52.  
53.     IF Radius = 0 THEN PSET (CX, CY), C: EXIT SUB
54.  
55.     ' Draw the middle span here so we don't draw it twice in the main loop,
56.     ' which would be a problem with blending turned on.
57.     LINE (CX - X, CY)-(CX + X, CY), C, BF
58.  
59.     WHILE X > Y
60.         RadiusError = RadiusError + Y * 2 + 1
61.         IF RadiusError >= 0 THEN
62.             IF X <> Y + 1 THEN
63.                 LINE (CX - Y, CY - X)-(CX + Y, CY - X), C, BF
64.                 LINE (CX - Y, CY + X)-(CX + Y, CY + X), C, BF
65.             END IF
66.             X = X - 1
67.             RadiusError = RadiusError - X * 2
68.         END IF
69.         Y = Y + 1
70.         LINE (CX - X, CY - Y)-(CX + X, CY - Y), C, BF
71.         LINE (CX - X, CY + Y)-(CX + X, CY + Y), C, BF
72.     WEND
73.  
74. END SUB
75.  
76. SUB NewCircleFill (cx AS INTEGER, cy AS INTEGER, r AS INTEGER, c AS _UNSIGNED LONG)
77.     DIM x AS INTEGER
78.     DIM y AS INTEGER
79.     DIM e AS INTEGER
80.  
81.     x = r
82.     e = -x
83.  
84.     DO WHILE x >= y
85.         LINE (cx - x, cy - y)-(cx + x, cy - y), c, BF
86.         IF y <> 0 THEN LINE (cx - x, cy + y)-(cx + x, cy + y), c, BF
87.  
88.         y = y + 1
89.         e = e + y + y
90.         IF e > 0 THEN
91.             x = x - 1
92.             e = e - x - x
93.         END IF
94.     LOOP
95.     x = r
96.     e = -x
97.     y = 0
98.  
99.     DO WHILE x >= y
100.         LINE (cx - y, cy - x)-(cx + y, cy - x), c, BF
101.         LINE (cx - y, cy + x)-(cx + y, cy + x), c, BF
102.         DO
103.             y = y + 1
104.             e = e + y + y
105.         LOOP UNTIL e > 0
106.         x = x - 1
107.         e = e - x - x
108.     LOOP
109. END SUB
110.  
111. SUB EllipseFill (cx AS INTEGER, cy AS INTEGER, rx AS INTEGER, ry AS INTEGER, c AS _UNSIGNED LONG)
112.     DIM a AS LONG, b AS LONG
113.     DIM x AS LONG, y AS LONG
114.     DIM xx AS LONG, yy AS LONG
115.     DIM sx AS LONG, sy AS LONG
116.     DIM e AS LONG
117.  
118.     a = 2 * rx * rx
119.     b = 2 * ry * ry
120.     x = rx
121.     xx = ry * ry * (1 - rx - rx)
122.     yy = rx * rx
123.     sx = b * rx
124.  
125.     DO WHILE sx >= sy
126.         LINE (cx - x, cy - y)-(cx + x, cy - y), c, BF
127.         IF y <> 0 THEN LINE (cx - x, cy + y)-(cx + x, cy + y), c, BF
128.  
129.         y = y + 1
130.         sy = sy + a
131.         e = e + yy
132.         yy = yy + a
133.  
134.         IF (e + e + xx) > 0 THEN
135.             x = x - 1
136.             sx = sx - b
137.             e = e + xx
138.             xx = xx + b
139.         END IF
140.     LOOP
141.  
142.     x = 0
143.     y = ry
144.     xx = rx * ry
145.     yy = rx * rx * (1 - ry - ry)
146.     e = 0
147.     sx = 1
148.     sy = a * ry
149.  
150.     DO WHILE sx <= sy
151.         LINE (cx - x, cy - y)-(cx + x, cy - y), c, BF
152.         LINE (cx - x, cy + y)-(cx + x, cy + y), c, BF
153.  
154.         DO
155.             x = x + 1
156.             sx = sx + b
157.             e = e + xx
158.             xx = xx + b
159.         LOOP UNTIL (e + e + yy) > 0
160.  
161.         y = y - 1
162.         sy = sy - a
163.         e = e + yy
164.         yy = yy + a
165.  
166.     LOOP
167.  
168. END SUB
169.  
170.  

I first test one drawing of each for alpha test, then I run them through long loops of redrawing for timed test.

BTW, the first CIRCLE just draws a circle to compare border edges to QB64's circle.