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| author | Robin Watts <robin.watts@artifex.com> | 2013-09-30 16:45:15 +0100 |
|---|---|---|
| committer | Robin Watts <robin.watts@artifex.com> | 2013-09-30 17:21:43 +0100 |
| commit | a8aec7875aaf6c8d8d4ed37ce74705988b73e9c1 (patch) | |
| tree | bf936a0aad19b0d1a84da538f57be8e0c772c3e7 /source/fitz/geometry.c | |
| parent | 9805dec32d8b7cb2fcc3251fdb670f5065e5f57e (diff) | |
| download | mupdf-a8aec7875aaf6c8d8d4ed37ce74705988b73e9c1.tar.xz | |
Bug 694526: Spot non-invertable matrices and bale before stroking
The bug fix added in the previous commit fails to work in this
case (hang-9527.pdf) because the matrix is not invertible and
hence the clipping rectangle ends up infinite. Spot this case
here and return early.
Diffstat (limited to 'source/fitz/geometry.c')
| -rw-r--r-- | source/fitz/geometry.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/source/fitz/geometry.c b/source/fitz/geometry.c index 81450246..c7c3d198 100644 --- a/source/fitz/geometry.c +++ b/source/fitz/geometry.c @@ -214,6 +214,25 @@ fz_invert_matrix(fz_matrix *dst, const fz_matrix *src) } int +fz_try_invert_matrix(fz_matrix *dst, const fz_matrix *src) +{ + /* Be careful to cope with dst == src */ + float a = src->a; + float det = a * src->d - src->b * src->c; + if (det >= -FLT_EPSILON && det <= FLT_EPSILON) + return 1; + det = 1 / det; + dst->a = src->d * det; + dst->b = -src->b * det; + dst->c = -src->c * det; + dst->d = a * det; + a = -src->e * dst->a - src->f * dst->c; + dst->f = -src->e * dst->b - src->f * dst->d; + dst->e = a; + return 0; +} + +int fz_is_rectilinear(const fz_matrix *m) { return (fabsf(m->b) < FLT_EPSILON && fabsf(m->c) < FLT_EPSILON) || |