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issue #364, clip procedure pos len conversion (3)

This commit is contained in:
kraus 2018-10-27 21:11:33 +02:00
parent 6102dcc7f7
commit 969c60d631
1 changed files with 0 additions and 58 deletions
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58
csrc/u8g2_hvline.c
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@ -47,61 +47,6 @@
/*
Description:
clip range from a (included) to b (excluded) agains c (included) to d (excluded)
Assumptions:
a <= b (violation is checked and handled correctly)
c <= d (this is not checked)
will return 0 if there is no intersection and if a > b
optimized clipping: c is set to 0 --> 27 Oct 2018: again removed the c==0 assumption
replaced by uint8_t u8g2_clip_intersection2
*/
static uint8_t u8g2_clip_intersection(u8g2_uint_t *ap, u8g2_uint_t *bp, u8g2_uint_t c, u8g2_uint_t d)
//static uint8_t u8g2_clip_intersection(u8g2_uint_t *ap, u8g2_uint_t *bp, u8g2_uint_t d)
{
u8g2_uint_t a = *ap;
u8g2_uint_t b = *bp;
/* handle the a>b case correctly. If code and time is critical, this could */
/* be removed completly (be aware about memory curruption for wrong */
/* arguments) or return 0 for a>b (will lead to skipped lines for wrong */
/* arguments) */
/* removing the following if clause completly may lead to memory corruption of a>b */
if ( a > b )
{
/* replacing this if with a simple "return 0;" will not handle the case with negative a */
if ( a < d )
{
b = d;
b--;
*bp = b;
}
else
{
a = c;
*ap = a;
}
}
/* from now on, the asumption a <= b is ok */
if ( a >= d )
return 0;
if ( b <= c )
return 0;
if ( a < c )
*ap = c;
if ( b > d )
*bp = d;
return 1;
}
/*
Description:
clip range from pos a (included) with line len (a+len excluded) agains c (included) to d (excluded)
@ -110,9 +55,6 @@ static uint8_t u8g2_clip_intersection(u8g2_uint_t *ap, u8g2_uint_t *bp, u8g2_uin
c <= d (this is not checked)
will return 0 if there is no intersection and if a > b
optimized clipping: c is set to 0 --> 27 Oct 2018: again removed the c==0 assumption
replaced by uint8_t u8g2_clip_intersection2
*/
static uint8_t u8g2_clip_intersection2(u8g2_uint_t *ap, u8g2_uint_t *len, u8g2_uint_t c, u8g2_uint_t d)