updated to latest openvr sdk, updated to use bindgen, ongoing refactoring

src/system.rs

@@ -0,0 +1,108 @@
+use openvr_sys;
+use openvr_sys::Enum_EGraphicsAPIConvention::*;
+use openvr_sys::Enum_ETrackingUniverseOrigin::*;
+
+use common::*;
+
+pub struct IVRSystem(*const ());
+
+impl IVRSystem {
+    pub unsafe fn from_raw(ptr: *const ()) -> Self {
+        IVRSystem(ptr as *mut ())
+    }
+
+    /// Get the recommended render target size
+    pub fn recommended_render_target_size(&self) -> Size {
+        unsafe {
+            let system = * { self.0 as *mut openvr_sys::Struct_VR_IVRSystem_FnTable };
+
+            let mut size = Size{width: 0, height: 0};
+            system.GetRecommendedRenderTargetSize.unwrap()(
+                &mut size.width,
+                &mut size.height
+            );
+            size
+        }
+    }
+
+
+    /// Get the projection matrix for an eye
+    /// supply the near and the far position
+    /// assumes opengl conventions
+    pub fn projection_matrix(&self, eye: Eye, near: f32, far: f32) -> [[f32; 4]; 4] {
+        unsafe {
+            let system = * { self.0 as *mut openvr_sys::Struct_VR_IVRSystem_FnTable };
+
+            let mat = system.GetProjectionMatrix.unwrap()(
+                eye.to_raw(),
+                near,
+                far,
+                EGraphicsAPIConvention_API_OpenGL
+            );
+            mat.m
+        }
+    }
+
+    /// Computes the distortion caused by the optics
+    pub fn compute_distortion(&self, eye: Eye, u: f32, v: f32) -> DistortionCoordinates {
+        unsafe {
+            let system = * { self.0 as *mut openvr_sys::Struct_VR_IVRSystem_FnTable };
+            let coord = system.ComputeDistortion.unwrap()(
+                eye.to_raw(),
+                u, v
+            );
+            DistortionCoordinates {
+                red: coord.rfRed,
+                blue: coord.rfBlue,
+                green: coord.rfGreen
+            }
+        }
+    }
+
+    /// Computes the distortion caused by the optics
+    pub fn eye_to_head_transform(&self, eye: Eye) -> [[f32; 4]; 3] {
+        unsafe {
+            let system = * { self.0 as *mut openvr_sys::Struct_VR_IVRSystem_FnTable };
+            let mat = system.GetEyeToHeadTransform.unwrap()(
+                eye.to_raw(),
+            );
+            mat.m
+        }
+    }
+
+    /// Computes the distortion caused by the optics
+    pub fn time_since_last_vsync(&self) -> Option<(f32, u64)> {
+        unsafe {
+            let system = * { self.0 as *mut openvr_sys::Struct_VR_IVRSystem_FnTable };
+            let mut frame = 0;
+            let mut sync = 0.;
+            let found = system.GetTimeSinceLastVsync.unwrap()(
+                &mut sync,
+                &mut frame
+            );
+
+            if found > 0 {
+                Some((sync, frame))
+            } else {
+                None
+            }
+        }
+    }
+
+    /// Fetch the tracked results from the HMD
+    pub fn tracked_devices(&self, time: f32) -> TrackedDevicePoses {
+        use std;
+
+        unsafe {
+            let system = * { self.0 as *mut openvr_sys::Struct_VR_IVRSystem_FnTable };
+            let mut data: [openvr_sys::TrackedDevicePose_t; 16] = std::mem::zeroed();
+            system.GetDeviceToAbsoluteTrackingPose.unwrap()(
+                ETrackingUniverseOrigin_TrackingUniverseSeated,
+                time,
+                &mut data[0],
+                16
+            );
+            to_tracked(data)
+        }
+    }
+}