I've written a TerrainClass that should randomly generate 2D terrain from a bunch of line segments. However, it just creates a single hill with a flat top.
Code:
| 1 | LineSegment::LineSegment(bool first) |
| 2 | { |
| 3 | if(first){ |
| 4 | sx = 0; |
| 5 | sy = (SCREEN_H/4); |
| 6 | ex = SCREEN_W; |
| 7 | ey = (SCREEN_H/4); |
| 8 | } |
| 9 | } |
| 10 | |
| 11 | void LineSegment::SetSegment(LineSegment *ParentSegment, int range) |
| 12 | /* Sets the (sx, sy) of this segment to |
| 13 | the (sx, sy) of the ParentSegment. After that, |
| 14 | it determines the midpoint of ParentSegment (mx, my) and |
| 15 | sets (ex, ey) of this segment to (mx, random range). |
| 16 | Finally, the (sx, sy) of ParentSegment is set to (ex, ey) |
| 17 | of this segment and the function exits */ |
| 18 | { |
| 19 | // set the start of this segment |
| 20 | sx = ParentSegment->sx; |
| 21 | sy = ParentSegment->sy; |
| 22 | |
| 23 | // find the midpoint of the parent segment |
| 24 | // on the x-axis |
| 25 | int mx = (ParentSegment->sx+ParentSegment->ex)/2; |
| 26 | |
| 27 | // the height of the new hill made |
| 28 | // by the setting of this segment |
| 29 | int my = (rand()%(range)-(range/2)); |
| 30 | |
| 31 | // stay within the min and max ranges |
| 32 | if(my > MAX_HEIGHT) my = MAX_HEIGHT; |
| 33 | if(my < MIN_HEIGHT) my = MIN_HEIGHT; |
| 34 | |
| 35 | // set the end of this line |
| 36 | // segment at the new midpoint |
| 37 | ex = mx; |
| 38 | ey = my; |
| 39 | |
| 40 | // set the beginning of ParentSegment to |
| 41 | // the end of this segment |
| 42 | ParentSegment->sx = ex; |
| 43 | ParentSegment->sy = ey; |
| 44 | |
| 45 | return; |
| 46 | } |
| 47 | //------------------------------------------------------ |
| 48 | //------------------------------------------------------ |
| 49 | |
| 50 | TerrainClass::TerrainClass() |
| 51 | /* Creates terrain from min to max with amount of hills */ |
| 52 | { |
| 53 | // create a bitmap to draw the terrain on |
| 54 | bmp = create_bitmap(SCREEN_W, MAX_HEIGHT); |
| 55 | |
| 56 | // set the initial segment (straight line) |
| 57 | segments[0] = new LineSegment(true); |
| 58 | cur_seg += 1; |
| 59 | |
| 60 | int segs_this_loop = 1; |
| 61 | int new_segs = 0; |
| 62 | |
| 63 | for(int i = 0; i < LOOP_ITERATIONS; i++){ |
| 64 | for(int j = 0; j < segs_this_loop; j++){ |
| 65 | segments[cur_seg] = new LineSegment(); |
| 66 | segments[cur_seg]->SetSegment(segments[j], 3); |
| 67 | cur_seg += 1; |
| 68 | new_segs += 1; |
| 69 | } |
| 70 | segs_this_loop += new_segs; |
| 71 | new_segs = 0; |
| 72 | } |
| 73 | |
| 74 | |
| 75 | for(int m = 0; m < segs_this_loop; m++) |
| 76 | line(bmp, segments[m]->sx, segments[m]->sy, |
| 77 | segments[m]->ex, segments[m]->ey, makecol(255,255,255)); |
| 78 | |
| 79 | } |
| 80 | //------------------------------------------------------ |
Is the problem in the loop or the SetSegment() function?
Edit: Oops, this probably would've fit better in the other forum. :$
Perhaps you could explain the algorithm, instead of letting us figure out the algo from your code.