Add CounterSampleBuffer::resolve_counter_range

Author: kvark

src/counters.rs

@@ -1,4 +1,5 @@
-use crate::MTLStorageMode;
+use crate::{MTLStorageMode, NSUInteger};
+use std::mem;
 
 /// See <https://developer.apple.com/documentation/metal/mtlcountersamplebufferdescriptor>
 pub enum MTLCounterSampleBufferDescriptor {}
@@ -63,6 +64,22 @@ foreign_obj_type! {
     pub struct CounterSampleBuffer;
 }
 
+impl CounterSampleBufferRef {
+    pub fn sample_count(&self) -> u64 {
+        unsafe { msg_send![self, sampleCount] }
+    }
+
+    pub fn resolve_counter_range(&self, range: crate::NSRange) -> Vec<NSUInteger> {
+        let mut data = vec![0 as NSUInteger; range.length as usize];
+        let total_bytes = range.length * mem::size_of::<NSUInteger>() as u64;
+        unsafe {
+            let ns_data: *mut crate::Object = msg_send![self, resolveCounterRange: range];
+            let () = msg_send![ns_data, getBytes: data.as_mut_ptr() length: total_bytes];
+        }
+        data
+    }
+}
+
 /// See <https://developer.apple.com/documentation/metal/mtlcounter>
 pub enum MTLCounter {}