Instead of relying on a scale which may increase rounding errors,
clip src by doing: src * (dst - clip) / dst and rounding the result
away from 1, so the new coordinates get closer to 1. We won't need
to fix up with a magic macro afterwards, because our scaling factor
will never go to the other side of 1.
Changes since v1:
- Adjust dst immediately, else drm_rect_width/height on dst gives bogus
results.
Change since v2:
- Get rid of macros and use 64-bits math.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
[mlankhorst: Add Villes comment, and rename newsrc to tmp. (Ville)]
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180503112217.37292-3-maarten.lankhorst@linux.intel.com
Allow the caller to specify a "prefix" string to drm_rect_debug_print()
to make it easier to see which drm_rect is being printed.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Add some helper functions to move drm_rects between different rotated
coordinate spaces. One function does the forward transform and
another does the inverse.
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Acked-by: Dave Airlie <airlied@linux.ie>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The 'struct' keyword was missing so struct drm_rect documentation never
ended up in the generated docs.
Also move the drm_rect documentations to a new section alognside the
various helper functions and add a short description about the intended
purpose of drm_rect.
v2: Move to new section and add general description
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
drm_rect_equals() tells whether two drm_rects are equal.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Add a debug function to print the rectangle in a human readable format.
v2: Renamed drm_region to drm_rect, the function from drm_region_debug
to drm_rect_debug_print(), and use %+d instead of +%d in the format.
v3: Use %d format for width/height in the non fixed point case as well
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
These functions calculate the scaling factor based on the source and
destination rectangles.
There are two version of the functions, the strict ones that will
return an error if the min/max scaling factor is exceeded, and the
relaxed versions that will adjust the src/dst rectangles in order to
keep the scaling factor withing the limits.
v2: Return error instead of adjusting regions, refactor common parts
into one function, and split into strict and relaxed versions.
v3: Renamed drm_region to drm_rect, add "_rect_" to the function
names.
v4: Fix "calculcate" typos
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
struct drm_rect represents a simple rectangle. The utility
functions are there to help driver writers.
v2: Moved the region stuff into its own file, made the smaller funcs
static inline, used 64bit maths in the scaled clipping function to
avoid overflows (instead it will saturate to INT_MIN or INT_MAX).
v3: Renamed drm_region to drm_rect, drm_region_clip to
drm_rect_intersect, and drm_region_subsample to drm_rect_downscale.
v4: Renamed some function parameters, improve kernel-doc comments a bit,
and actually generate documentation for drm_rect.[ch].
v5: s/RETUTRNS/RETURNS/
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
