Fix display projections when translated.

There are two different translations to apply in the logical
orientation, one before scaling and one after.
So translate, scale, translate then rotate.

Bug: 7139798
Change-Id: I0726991cadb62988390e77503dbbaed54f07bfe3

2 files changed, 14 insertions, 11 deletions

diff --git a/services/surfaceflinger/DisplayDevice.cpp b/services/surfaceflinger/DisplayDevice.cpp
index 6a9cb3e..2c06a0b 100644
--- a/services/surfaceflinger/DisplayDevice.cpp
+++ b/services/surfaceflinger/DisplayDevice.cpp
@@ -309,7 +309,7 @@ void DisplayDevice::setProjection(int orientation,
 void DisplayDevice::updateGeometryTransform() {
     int w = mDisplayWidth;
     int h = mDisplayHeight;
-    Transform T, R, S;
+    Transform TL, TP, R, S;
     if (DisplayDevice::orientationToTransfrom(
             mOrientation, w, h, &R) == NO_ERROR) {
         dirtyRegion.set(bounds());
@@ -350,13 +350,12 @@ void DisplayDevice::updateGeometryTransform() {
         float src_y = viewport.top;
         float dst_x = frame.left;
         float dst_y = frame.top;
-        float tx = dst_x - src_x;
-        float ty = dst_y - src_y;
-        T.set(tx, ty);
-
-        // The viewport and frame are both in the logical orientation, so the
-        // translation is also in that space. So translation must be applied
-        // before rotating from logical to physical orientation.
-        mGlobalTransform = S * R * T;
+        TL.set(-src_x, -src_y);
+        TP.set(dst_x, dst_y);
+
+        // The viewport and frame are both in the logical orientation.
+        // Apply the logical translation, scale to physical size, apply the
+        // physical translation and finally rotate to the physical orientation.
+        mGlobalTransform = R * TP * S * TL;
     }
 }
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 6542acd..da15248 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -1976,7 +1976,8 @@ void SurfaceFlinger::dumpAllLocked(
         snprintf(buffer, SIZE,
                 "+ DisplayDevice[%u]\n"
                 "   type=%x, layerStack=%u, (%4dx%4d), orient=%2d (type=%08x), "
-                "flips=%u, secure=%d, numLayers=%u, v:[%d,%d,%d,%d], f:[%d,%d,%d,%d]\n",
+                "flips=%u, secure=%d, numLayers=%u, v:[%d,%d,%d,%d], f:[%d,%d,%d,%d], "
+                "transform:[[%0.3f,%0.3f,%0.3f][%0.3f,%0.3f,%0.3f][%0.3f,%0.3f,%0.3f]]\n",
                 dpy,
                 hw->getDisplayType(), hw->getLayerStack(),
                 hw->getWidth(), hw->getHeight(),
@@ -1985,7 +1986,10 @@ void SurfaceFlinger::dumpAllLocked(
                 hw->getSecureLayerVisible(),
                 hw->getVisibleLayersSortedByZ().size(),
                 hw->getViewport().left, hw->getViewport().top, hw->getViewport().right, hw->getViewport().bottom,
-                hw->getFrame().left, hw->getFrame().top, hw->getFrame().right, hw->getFrame().bottom);
+                hw->getFrame().left, hw->getFrame().top, hw->getFrame().right, hw->getFrame().bottom,
+                hw->getTransform()[0][0], hw->getTransform()[1][0], hw->getTransform()[2][0],
+                hw->getTransform()[0][1], hw->getTransform()[1][1], hw->getTransform()[2][1],
+                hw->getTransform()[0][2], hw->getTransform()[1][2], hw->getTransform()[2][2]);
 
         result.append(buffer);
     }