Make PresentMode configurable

Disable vsync

Revert accidential hardcode of num_frames

Make the PresentMode configurable

Adapt examples
+ adjust style according to @kvrak

Adher to @kvarks wishes for style.

Examples build.

Fix unnecessary ampersand.

examples/hello_triangle_c/main.c

@@ -197,6 +197,7 @@ int main() {
             .format = WGPUTextureFormat_Bgra8Unorm,
             .width = prev_width,
             .height = prev_height,
+            .present_mode = WGPUPresentMode_Vsync,
         });
 
     while (!glfwWindowShouldClose(window)) {
@@ -213,6 +214,7 @@ int main() {
                     .format = WGPUTextureFormat_Bgra8Unorm,
                     .width = width,
                     .height = height,
+                    .present_mode = WGPUPresentMode_Vsync,
                 });
         }
 

ffi/wgpu.h

@@ -1,6 +1,6 @@
 #define WGPU_LOCAL
 
-/* Generated with cbindgen:0.8.7 */
+/* Generated with cbindgen:0.9.0 */
 
 #include <stdarg.h>
 #include <stdbool.h>
@@ -110,6 +110,11 @@ typedef enum {
   WGPUPowerPreference_HighPerformance = 2,
 } WGPUPowerPreference;
 
+typedef enum {
+  WGPUPresentMode_NoVsync = 0,
+  WGPUPresentMode_Vsync = 1,
+} WGPUPresentMode;
+
 typedef enum {
   WGPUPrimitiveTopology_PointList = 0,
   WGPUPrimitiveTopology_LineList = 1,
@@ -577,6 +582,7 @@ typedef struct {
   WGPUTextureFormat format;
   uint32_t width;
   uint32_t height;
+  WGPUPresentMode present_mode;
 } WGPUSwapChainDescriptor;
 
 typedef struct {

wgpu-native/src/device.rs

@@ -1734,6 +1734,10 @@ pub fn device_create_swap_chain(
     );
     //TODO: check for supported
     config.composite_alpha = hal::window::CompositeAlpha::OPAQUE;
+    config.present_mode = match desc.present_mode {
+        swap_chain::PresentMode::NoVsync => hal::PresentMode::Immediate,
+        swap_chain::PresentMode::Vsync => hal::PresentMode::Fifo,
+    };
 
     if let Some(formats) = formats {
         assert!(

wgpu-native/src/swap_chain.rs

@@ -77,6 +77,13 @@ pub struct SwapChain<B: hal::Backend> {
     pub(crate) command_pool: hal::CommandPool<B, hal::General>,
 }
 
+#[repr(C)]
+#[derive(Copy, Clone, Debug)]
+pub enum PresentMode {
+    NoVsync = 0,
+    Vsync = 1,
+}
+
 #[repr(C)]
 #[derive(Clone, Debug)]
 pub struct SwapChainDescriptor {
@@ -84,6 +91,7 @@ pub struct SwapChainDescriptor {
     pub format: resource::TextureFormat,
     pub width: u32,
     pub height: u32,
+    pub present_mode: PresentMode,
 }
 
 impl SwapChainDescriptor {