diff options
| author | Chris Wilson <chris@chris-wilson.co.uk> | 2010-03-03 21:25:11 +0000 |
|---|---|---|
| committer | Chris Wilson <chris@chris-wilson.co.uk> | 2010-03-04 00:04:30 +0000 |
| commit | 5b973c670807bda2bb355c90ea817e2a2f092f0b (patch) | |
| tree | 10be290b1cc8c6636a08edd9fb2f03c6b98738db /src/drm | |
| parent | 404ead7eebafa7ca077e1d012dde0a598b64245a (diff) | |
drm/i915: Fix crash with linear-step-function
Avoid the potential divide by zero by falling back to pixman rendered
gradient textures for such troublesome input.
Diffstat (limited to 'src/drm')
| -rw-r--r-- | src/drm/cairo-drm-i915-shader.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/src/drm/cairo-drm-i915-shader.c b/src/drm/cairo-drm-i915-shader.c index a1bb9bfb..98a31d62 100644 --- a/src/drm/cairo-drm-i915-shader.c +++ b/src/drm/cairo-drm-i915-shader.c @@ -985,7 +985,7 @@ i915_set_shader_program (i915_device_t *device, FS_END (); } -static void +static cairo_bool_t i915_shader_linear_init (struct i915_shader_linear *l, const cairo_linear_pattern_t *linear) { @@ -994,9 +994,12 @@ i915_shader_linear_init (struct i915_shader_linear *l, dx = _cairo_fixed_to_double (linear->p2.x - linear->p1.x); dy = _cairo_fixed_to_double (linear->p2.y - linear->p1.y); - sf = 1. / (dx * dx + dy * dy); - dx *= sf; - dy *= sf; + sf = dx * dx + dy * dy; + if (sf <= 1e-5) + return FALSE; + + dx /= sf; + dy /= sf; x0 = _cairo_fixed_to_double (linear->p1.x); y0 = _cairo_fixed_to_double (linear->p1.y); @@ -1015,6 +1018,8 @@ i915_shader_linear_init (struct i915_shader_linear *l, l->dy = m.xy; l->offset = m.x0; } + + return TRUE; } static cairo_bool_t @@ -1130,8 +1135,8 @@ i915_shader_acquire_linear (i915_shader_t *shader, cairo_bool_t mode = LINEAR_TEXTURE; cairo_status_t status; - i915_shader_linear_init (&src->linear, linear); - if (linear->base.n_stops == 2 && + if (i915_shader_linear_init (&src->linear, linear) && + linear->base.n_stops == 2 && linear->base.stops[0].offset == 0.0 && linear->base.stops[1].offset == 1.0) { |