From: Ville Syrjälä ville.syrjala@linux.intel.com
struct drm_region represents a two dimensional region. The utility functions are there to help driver writers.
Signed-off-by: Ville Syrjälä ville.syrjala@linux.intel.com --- drivers/gpu/drm/drm_crtc_helper.c | 156 +++++++++++++++++++++++++++++++++++++ include/drm/drm_crtc_helper.h | 24 ++++++ 2 files changed, 180 insertions(+), 0 deletions(-)
diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c index af5a8f0..f311c21 100644 --- a/drivers/gpu/drm/drm_crtc_helper.c +++ b/drivers/gpu/drm/drm_crtc_helper.c @@ -1224,3 +1224,159 @@ int drm_framebuffer_check(const struct drm_mode_fb_cmd2 *r, unsigned int size) return 0; } EXPORT_SYMBOL(drm_framebuffer_check); + + +/** + * drm_region_adjust_size - adjust the size of the region + * @r: region to be adjusted + * @x: horizontal adjustment + * @y: vertical adjustment + * + * Change the size of region @r by @x in the horizontal direction, + * and by @y in the vertical direction, while keeping the center + * of @r stationary. + * + * Positive @x and @y increase the size, negative values decrease it. + */ +void drm_region_adjust_size(struct drm_region *r, int x, int y) +{ + r->x1 -= x >> 1; + r->y1 -= y >> 1; + r->x2 += (x + 1) >> 1; + r->y2 += (y + 1) >> 1; +} +EXPORT_SYMBOL(drm_region_adjust_size); + +/** + * drm_region_translate - translate the region + * @r: region to be tranlated + * @x: horizontal translation + * @y: vertical translation + * + * Move region @r by @x in the horizontal direction, + * and by @y in the vertical direction. + */ +void drm_region_translate(struct drm_region *r, int x, int y) +{ + r->x1 += x; + r->y1 += y; + r->x2 += x; + r->y2 += y; +} +EXPORT_SYMBOL(drm_region_translate); + +/** + * drm_region_subsample - subsample a region + * @r: region to be subsampled + * @hsub: horizontal subsampling factor + * @vsub: vertical subsampling factor + * + * Divide the coordinates of region @r by @hsub and @vsub. + */ +void drm_region_subsample(struct drm_region *r, int hsub, int vsub) +{ + r->x1 /= hsub; + r->y1 /= vsub; + r->x2 /= hsub; + r->y2 /= vsub; +} +EXPORT_SYMBOL(drm_region_subsample); + +/** + * drm_region_width - determine the region width + * @r: region whose width is returned + * + * RETURNS: + * The width of the region. + */ +int drm_region_width(const struct drm_region *r) +{ + return r->x2 - r->x1; +} +EXPORT_SYMBOL(drm_region_width); + +/** + * drm_region_height - determine the region height + * @r: region whose height is returned + * + * RETURNS: + * The height of the region. + */ +int drm_region_height(const struct drm_region *r) +{ + return r->y2 - r->y1; +} +EXPORT_SYMBOL(drm_region_height); + +/** + * drm_region_visible - determine if the the region is visible + * @r: region whose visibility is returned + * + * RETURNS: + * @true if the region is visible, @false otherwise. + */ +bool drm_region_visible(const struct drm_region *r) +{ + return drm_region_width(r) > 0 && drm_region_height(r) > 0; +} +EXPORT_SYMBOL(drm_region_visible); + +/** + * drm_region_clip - clip one region by another region + * @r: region to be clipped + * @clip: clip region + * + * Clip region @r by region @clip. + * + * RETURNS: + * @true if the region is still visible after being clipped, + * @false otherwise. + */ +bool drm_region_clip(struct drm_region *r, const struct drm_region *clip) +{ + r->x1 = max(r->x1, clip->x1); + r->y1 = max(r->y1, clip->y1); + r->x2 = min(r->x2, clip->x2); + r->y2 = min(r->y2, clip->y2); + + return drm_region_visible(r); +} +EXPORT_SYMBOL(drm_region_clip); + +/** + * drm_region_clip_scaled - perform a scaled clip operation + * @src: source window region + * @dst: destination window region + * @clip: clip region + * @hscale: horizontal scaling factor + * @vscale: vertical scaling factor + * + * Clip region @dst by region @clip. Clip region @src by the same + * amounts multiplied by @hscale and @vscale. + * + * RETUTRNS: + * @true if region @dst is still visible after being clipped, + * @false otherwise + */ +bool drm_region_clip_scaled(struct drm_region *src, struct drm_region *dst, + const struct drm_region *clip, + int hscale, int vscale) +{ + int diff; + + diff = clip->x1 - dst->x1; + if (diff > 0) + src->x1 += diff * hscale; + diff = clip->y1 - dst->y1; + if (diff > 0) + src->y1 += diff * vscale; + diff = dst->x2 - clip->x2; + if (diff > 0) + src->x2 -= diff * hscale; + diff = dst->y2 - clip->y2; + if (diff > 0) + src->y2 -= diff * vscale; + + return drm_region_clip(dst, clip); +} +EXPORT_SYMBOL(drm_region_clip_scaled); diff --git a/include/drm/drm_crtc_helper.h b/include/drm/drm_crtc_helper.h index 4d2a53a..e1295c7 100644 --- a/include/drm/drm_crtc_helper.h +++ b/include/drm/drm_crtc_helper.h @@ -154,4 +154,28 @@ extern int drm_format_vert_chroma_subsampling(uint32_t format); extern int drm_framebuffer_check(const struct drm_mode_fb_cmd2 *r, unsigned int size);
+/** + * drm_region - two dimensional region + * @x1: horizontal starting coordinate (inclusive) + * @x2: horizontal ending coordinate (exclusive) + * @y1: vertical starting coordinate (inclusive) + * @y2: vertical ending coordinate (exclusive) + */ +struct drm_region { + int x1, y1, x2, y2; +}; + +extern void drm_region_adjust_size(struct drm_region *r, int x, int y); +extern void drm_region_translate(struct drm_region *r, int x, int y); +extern void drm_region_subsample(struct drm_region *r, int hsub, int vsub); +extern int drm_region_width(const struct drm_region *r); +extern int drm_region_height(const struct drm_region *r); +extern bool drm_region_visible(const struct drm_region *r); +extern bool drm_region_clip(struct drm_region *r, + const struct drm_region *clip); +extern bool drm_region_clip_scaled(struct drm_region *src, + struct drm_region *dst, + const struct drm_region *clip, + int hscale, int vscale); + #endif