Diagonal Gradient

[keybone]

Post Deleted

[bplus]

Oh that's nice! I think there is a nice trick or lesson in there.

[bplus]

I am amazed that all those lines are drawing perfectly without overlap, even when I mess with their slant.

Here is an interesting Interference pattern using gradients:

Code: QB64: [Select]

1. _TITLE "Interesting Interference Pattern"
2. 'Bplus mod of diagonal gradient by keybone 2018-08-03
3. SCREEN _NEWIMAGE(799, 631, 32)
4. _SCREENMOVE 150, 40
5. d = 1
6. WHILE NOT _KEYDOWN(27)
7.     CLS
8.     gradientDiagonal 0, 0, _WIDTH, _HEIGHT, _RGB(255, 128, 0), _RGB(0, 128, 255), 255
9.     stepper = stepper + 1 * d
10.     IF stepper > 100 THEN stepper = 100: d = d * -1
11.     IF stepper < -100 THEN stepper = -100: d = d * -1
12.     FOR r = 1 TO 300 STEP 9
13.         'CIRCLE (799 / 2 + stepper, 631 / 2), r, _RGB32(255)
14.         CIRCLE (799 / 2 + stepper, 631 / 2), r, _RGB32(128, 0, 0)
15.         CIRCLE (799 / 2 + stepper, 631 / 2), r + 3, _RGB32(0, 128, 0)
16.         CIRCLE (799 / 2 + stepper, 631 / 2), r + 6, _RGB32(0, 0, 128)
17.     NEXT
18.     _DISPLAY
19.     _LIMIT 20
20. WEND
21.  
22. SUB gradientDiagonal (x0, y0, w, h, c1 AS _UNSIGNED LONG, c2 AS _UNSIGNED LONG, a AS _UNSIGNED _BYTE)
23.     DIM mr AS DOUBLE, mg AS DOUBLE, mb AS DOUBLE
24.     dw = w + h
25.     mr = (_RED(c2) - _RED(c1)) / dw
26.     mg = (_GREEN(c2) - _GREEN(c1)) / dw
27.     mb = (_BLUE(c2) - _BLUE(c1)) / dw
28.     FOR d = 0 TO dw - 1 STEP 5
29.         r = _RED(c2) + (d - dw) * mr
30.         g = _GREEN(c2) + (d - dw) * mg
31.         b = _BLUE(c2) + (d - dw) * mb
32.         IF d <= h - 1 THEN
33.             LINE (x0 + d, y0)-(x0, y0 + d), _RGBA32(r, g, b, a)
34.         ELSEIF d >= h AND d <= w - 1 THEN
35.             LINE (x0 + d, y0)-(x0 + (d - h), y0 + h), _RGBA32(r, g, b, a)
36.         ELSEIF d >= w AND d <= dw - 1 THEN
37.             LINE (x0 + w, y0 + (d - w))-(x0 + (d - h), y0 + h), _RGBA32(r, g, b, a)
38.         END IF
39.     NEXT d
40. END SUB
41.  

I remember spending quite some time trying to figure out how to draw a grid of diagonal lines.
Now I have another idea for mod... :)

[bplus]

OH! They are all perfect because they are all 45 degrees! Aha!