Line rasterization will make one pixel error. See graph http://bbs.chinagamedev.net/attachment.php?attachmentid=3356&stc=1.
There are many lines exceeding X axis, though they have the end point with Y=0.
Please look at the following data. Half of them have the end point with Y=0:
0.089999999999999997,0.000000000000000000 - 0.100000000000000010,0.010000000000000009
0.095000000000000001,0.000000000000000000 - 0.100000000000000010,0.005000000000000004
Why they like exceeding X axis?
How can I solve this issue?
Thaks in advance.
======== bd3e028
0.000000000000000014,0.095000000000000015 - 0.005000000000000018,0.100000000000000020
-0.000000000000000014,0.089999999999999983 - 0.010000000000000023,0.100000000000000020
0.000000000000000000,0.085000000000000006 - 0.015000000000000013,0.100000000000000020
0.000000000000000000,0.080000000000000002 - 0.020000000000000018,0.100000000000000020
0.000000000000000000,0.074999999999999997 - 0.025000000000000022,0.100000000000000020
0.000000000000000000,0.070000000000000007 - 0.030000000000000013,0.100000000000000020
0.000000000000000000,0.065000000000000002 - 0.035000000000000017,0.100000000000000020
0.000000000000000000,0.059999999999999998 - 0.040000000000000022,0.100000000000000020
0.000000000000000000,0.055000000000000000 - 0.045000000000000019,0.100000000000000020
0.000000000000000007,0.050000000000000010 - 0.050000000000000017,0.100000000000000020
-0.000000000000000007,0.044999999999999991 - 0.055000000000000021,0.100000000000000020
0.000000000000000000,0.040000000000000001 - 0.060000000000000019,0.100000000000000020
0.000000000000000000,0.035000000000000003 - 0.065000000000000016,0.100000000000000020
0.000000000000000000,0.029999999999999999 - 0.070000000000000021,0.100000000000000020
0.000000000000000003,0.025000000000000005 - 0.075000000000000011,0.100000000000000020
0.000000000000000000,0.020000000000000000 - 0.080000000000000016,0.100000000000000020
0.000000000000000000,0.014999999999999999 - 0.085000000000000020,0.100000000000000020
0.000000000000000000,0.010000000000000000 - 0.090000000000000024,0.100000000000000020
0.000000000000000000,0.005000000000000000 - 0.095000000000000015,0.100000000000000020
0.000000000000000000,0.000000000000000000 - 0.100000000000000020,0.100000000000000020
0.005000000000000000,0.000000000000000000 - 0.100000000000000020,0.095000000000000015
0.010000000000000000,0.000000000000000000 - 0.100000000000000010,0.090000000000000011
0.014999999999999999,0.000000000000000000 - 0.100000000000000010,0.085000000000000006
0.020000000000000000,0.000000000000000000 - 0.100000000000000010,0.080000000000000002
0.025000000000000001,0.000000000000000000 - 0.100000000000000010,0.075000000000000011
0.029999999999999999,0.000000000000000000 - 0.100000000000000010,0.070000000000000007
0.035000000000000003,0.000000000000000000 - 0.100000000000000010,0.065000000000000002
0.040000000000000001,0.000000000000000000 - 0.100000000000000010,0.060000000000000005
0.044999999999999998,0.000000000000000000 - 0.100000000000000010,0.055000000000000014
0.050000000000000003,0.000000000000000000 - 0.100000000000000010,0.050000000000000010
0.055000000000000000,0.000000000000000000 - 0.100000000000000010,0.045000000000000005
0.059999999999999998,0.000000000000000000 - 0.100000000000000010,0.040000000000000008
0.065000000000000002,0.000000000000000000 - 0.100000000000000010,0.035000000000000010
0.070000000000000007,0.000000000000000000 - 0.100000000000000010,0.029999999999999999
0.074999999999999997,0.000000000000000000 - 0.100000000000000010,0.025000000000000012
0.080000000000000002,0.000000000000000000 - 0.100000000000000010,0.020000000000000007
0.085000000000000006,0.000000000000000000 - 0.100000000000000010,0.015000000000000001
0.089999999999999997,0.000000000000000000 - 0.100000000000000010,0.010000000000000009
0.095000000000000001,0.000000000000000000 - 0.100000000000000010,0.005000000000000004