hwc: Support odd-sized dockable layers

During transition effects Android framework may rescale
dockable layers, and resulting window size may have an odd
width or height. If the layer is significantly upscaled on
external display, the rounding error of integer division
will be blown up and may shift the adjusted overlay window
by few pixels.

Change-Id: Ib4034f4a34bb81e02fbcdb3c709c91dfb853bfaa
Signed-off-by: Mykola Ostrovskyy <mykola@ti.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/hwc/hwc.c b/hwc/hwc.c
index 81032e9..29ffdac 100644
--- a/hwc/hwc.c
+++ b/hwc/hwc.c
@@ -639,7 +639,7 @@ static void omap4_hwc_setup_layer(omap4_hwc_device_t *hwc_dev, struct dss2_ovl_i
 
 const float m_unit[2][3] = { { 1., 0., 0. }, { 0., 1., 0. } };
 
-static inline void m_translate(float m[2][3], int dx, int dy)
+static inline void m_translate(float m[2][3], float dx, float dy)
 {
     m[0][2] += dx;
     m[1][2] += dy;
@@ -718,7 +718,7 @@ static void set_ext_matrix(omap4_hwc_ext_t *ext, struct hwc_rect region)
        m = (center-from-target-center) * (scale-to-target) * (mirror) * (rotate) * (center-to-original-center) */
 
     memcpy(ext->m, m_unit, sizeof(m_unit));
-    m_translate(ext->m, -(orig_w >> 1) - region.left, -(orig_h >> 1) - region.top);
+    m_translate(ext->m, -(orig_w / 2.0f) - region.left, -(orig_h / 2.0f) - region.top);
     m_rotate(ext->m, ext->current.rotation);
     if (ext->current.hflip)
         m_scale(ext->m, 1, -1, 1, 1);