From b82a7ff370573e23b1cb931d44eea734cbd463b8 Mon Sep 17 00:00:00 2001
From: Jules Youngberg <julesdayoungberg@gmail.com>
Date: Wed, 15 Jun 2022 20:01:41 -0700
Subject: [PATCH] embrace raw pointers for ffi

---
 src/bindings.rs | 74 ++-----------------------------------------------
 src/lib.rs      | 33 +++++++++++-----------
 2 files changed, 20 insertions(+), 87 deletions(-)

diff --git a/src/bindings.rs b/src/bindings.rs
index 28a0b60..e3ad258 100644
--- a/src/bindings.rs
+++ b/src/bindings.rs
@@ -116,75 +116,6 @@ fn bindgen_test_layout_mediagraph_Output() {
     );
 }
 #[repr(C)]
-#[derive(Debug, Copy, Clone)]
-pub struct mediagraph_Feature {
-    pub data: *mut mediagraph_Landmark,
-}
-#[test]
-fn bindgen_test_layout_mediagraph_Feature() {
-    assert_eq!(
-        ::std::mem::size_of::<mediagraph_Feature>(),
-        8usize,
-        concat!("Size of: ", stringify!(mediagraph_Feature))
-    );
-    assert_eq!(
-        ::std::mem::align_of::<mediagraph_Feature>(),
-        8usize,
-        concat!("Alignment of ", stringify!(mediagraph_Feature))
-    );
-    assert_eq!(
-        unsafe { &(*(::std::ptr::null::<mediagraph_Feature>())).data as *const _ as usize },
-        0usize,
-        concat!(
-            "Offset of field: ",
-            stringify!(mediagraph_Feature),
-            "::",
-            stringify!(data)
-        )
-    );
-}
-#[repr(C)]
-#[derive(Debug, Copy, Clone)]
-pub struct mediagraph_FeatureList {
-    pub num_features: u8,
-    pub features: *mut mediagraph_Feature,
-}
-#[test]
-fn bindgen_test_layout_mediagraph_FeatureList() {
-    assert_eq!(
-        ::std::mem::size_of::<mediagraph_FeatureList>(),
-        16usize,
-        concat!("Size of: ", stringify!(mediagraph_FeatureList))
-    );
-    assert_eq!(
-        ::std::mem::align_of::<mediagraph_FeatureList>(),
-        8usize,
-        concat!("Alignment of ", stringify!(mediagraph_FeatureList))
-    );
-    assert_eq!(
-        unsafe {
-            &(*(::std::ptr::null::<mediagraph_FeatureList>())).num_features as *const _ as usize
-        },
-        0usize,
-        concat!(
-            "Offset of field: ",
-            stringify!(mediagraph_FeatureList),
-            "::",
-            stringify!(num_features)
-        )
-    );
-    assert_eq!(
-        unsafe { &(*(::std::ptr::null::<mediagraph_FeatureList>())).features as *const _ as usize },
-        8usize,
-        concat!(
-            "Offset of field: ",
-            stringify!(mediagraph_FeatureList),
-            "::",
-            stringify!(features)
-        )
-    );
-}
-#[repr(C)]
 pub struct mediagraph_Detector__bindgen_vtable(::std::os::raw::c_void);
 #[repr(C)]
 #[derive(Debug)]
@@ -227,13 +158,14 @@ extern "C" {
     pub fn mediagraph_Detector_Detector_destructor(this: *mut mediagraph_Detector);
 }
 extern "C" {
-    #[link_name = "\u{1}__ZN10mediagraph8Detector7ProcessEPhii"]
+    #[link_name = "\u{1}__ZN10mediagraph8Detector7ProcessEPhiiS1_"]
     pub fn mediagraph_Detector_Process(
         this: *mut ::std::os::raw::c_void,
         data: *mut u8,
         width: ::std::os::raw::c_int,
         height: ::std::os::raw::c_int,
-    ) -> *mut mediagraph_FeatureList;
+        num_features: *mut u8,
+    ) -> *mut mediagraph_Landmark;
 }
 #[repr(C)]
 pub struct mediagraph_Effect__bindgen_vtable(::std::os::raw::c_void);
diff --git a/src/lib.rs b/src/lib.rs
index a5bd362..14d7e15 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -24,8 +24,6 @@ use bindings::*;
 
 type mFeatureType = mediagraph_FeatureType;
 type mOutput = mediagraph_Output;
-type mFeature = mediagraph_Feature;
-type mFeatureList = mediagraph_FeatureList;
 
 /// The type of visual feature made up of landmarks.
 #[derive(Debug, Clone, Copy)]
@@ -161,33 +159,36 @@ impl Detector {
     /// Processes the input frame, returns a slice of landmarks if any are detected.
     pub fn process(&mut self, input: &Mat) -> Vec<Vec<Vec<Landmark>>> {
         let mut data = input.clone();
+        let mut num_features = vec![0; self.outputs.len()];
+
         let results = unsafe {
+            let nf_data = num_features.as_mut_slice();
             mediagraph_Detector_Process(
                 self.graph as *mut std::ffi::c_void,
                 data.data_mut(),
                 data.cols(),
                 data.rows(),
+                nf_data.as_mut_ptr(),
             )
         };
 
         let mut landmarks = vec![];
+        let mut data_index = 0;
 
-        let feature_lists =
-            unsafe { std::slice::from_raw_parts(results, self.outputs.len() as usize) };
-
-        for (i, feature_list) in feature_lists.iter().enumerate() {
-            let num_landmarks = self.outputs[i].type_.num_landmarks();
+        for (i, &count) in num_features.iter().enumerate() {
             let mut fl = vec![];
-            let features = unsafe {
-                std::slice::from_raw_parts(
-                    feature_list.features,
-                    feature_list.num_features as usize,
-                )
-            };
+            if count == 0 {
+                landmarks.push(fl);
+                continue;
+            }
 
-            for feature in features.iter() {
-                let landmarks = unsafe { std::slice::from_raw_parts(feature.data, num_landmarks) };
-                fl.push(landmarks.to_vec());
+            let num_landmarks = self.outputs[i].type_.num_landmarks();
+
+            for _ in 0..count {
+                let l =
+                    unsafe { std::slice::from_raw_parts(results.add(data_index), num_landmarks) };
+                data_index += num_landmarks;
+                fl.push(l.to_vec());
             }
 
             landmarks.push(fl);