GPU Display: Some fixes to alternate camera modes (ctrl / alt pressed)

Author: davidrohr

GPU/GPUTracking/display/GPUDisplay.cxx

@@ -1542,7 +1542,10 @@ int GPUDisplay::DrawGLScene_internal(bool mixAnimation, float mAnimateTime)
       mXYZ[2] = r2 * sinf(phi);
       mXYZ[1] = r * sinf(theta);
 
-      nextViewMatrix = HMM_LookAt({mXYZ[0], mXYZ[1], mXYZ[2]}, {0, 0, 0}, {0, 1, 0});
+      if (yUp) {
+        nextViewMatrix = MY_HMM_IDENTITY;
+      }
+      nextViewMatrix = nextViewMatrix * HMM_LookAt({mXYZ[0], mXYZ[1], mXYZ[2]}, {0, 0, 0}, {0, 1, 0});
     } else {
       nextViewMatrix = nextViewMatrix * HMM_Translate({moveX, moveY, moveZ});
       if (rotYaw != 0.f) {

GPU/GPUTracking/display/GPUDisplayBackendX11.cxx

@@ -36,7 +36,7 @@ int GPUDisplayBackendX11::GetKey(int key)
   if (key == 65505 || key == 65506) {
     return (KEY_SHIFT);
   }
-  if (key == 65513 || key == 65027) {
+  if (key == 65513 || key == 65027 || key == 65511) {
     return (KEY_ALT);
   }
   if (key == 65507 || key == 65508) {