diff --git a/Cargo.lock b/Cargo.lock
index e7b2462..62ee113 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -252,7 +252,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "gfx-backend-dx12"
 version = "0.1.0"
-source = "git+https://github.com/gfx-rs/gfx#f10a8fb4eda0e899a9e3e35777ebf0517b0fc77d"
+source = "git+https://github.com/gfx-rs/gfx#8d2b93a8dfd9c99b7cbec703924a628d56cc9c73"
 dependencies = [
  "bitflags 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "derivative 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -268,7 +268,7 @@ dependencies = [
 [[package]]
 name = "gfx-backend-metal"
 version = "0.1.0"
-source = "git+https://github.com/gfx-rs/gfx#f10a8fb4eda0e899a9e3e35777ebf0517b0fc77d"
+source = "git+https://github.com/gfx-rs/gfx#8d2b93a8dfd9c99b7cbec703924a628d56cc9c73"
 dependencies = [
  "block 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "cocoa 0.15.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -288,7 +288,7 @@ dependencies = [
 [[package]]
 name = "gfx-backend-vulkan"
 version = "0.1.0"
-source = "git+https://github.com/gfx-rs/gfx#f10a8fb4eda0e899a9e3e35777ebf0517b0fc77d"
+source = "git+https://github.com/gfx-rs/gfx#8d2b93a8dfd9c99b7cbec703924a628d56cc9c73"
 dependencies = [
  "ash 0.24.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -306,7 +306,7 @@ dependencies = [
 [[package]]
 name = "gfx-hal"
 version = "0.1.0"
-source = "git+https://github.com/gfx-rs/gfx#f10a8fb4eda0e899a9e3e35777ebf0517b0fc77d"
+source = "git+https://github.com/gfx-rs/gfx#8d2b93a8dfd9c99b7cbec703924a628d56cc9c73"
 dependencies = [
  "bitflags 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "failure 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/libportability-gfx/src/impls.rs b/libportability-gfx/src/impls.rs
index 85a1edb..9c399e6 100644
--- a/libportability-gfx/src/impls.rs
+++ b/libportability-gfx/src/impls.rs
@@ -2715,18 +2715,19 @@ pub extern "C" fn gfxCmdSetDepthBias(
 }
 #[inline]
 pub extern "C" fn gfxCmdSetBlendConstants(
-    _commandBuffer: VkCommandBuffer,
-    _blendConstants: *const f32,
+    mut commandBuffer: VkCommandBuffer,
+    blendConstants: *const f32,
 ) {
-    unimplemented!()
+    let value = unsafe { *(blendConstants as *const hal::pso::ColorValue) };
+    commandBuffer.set_blend_constants(value);
 }
 #[inline]
 pub extern "C" fn gfxCmdSetDepthBounds(
-    _commandBuffer: VkCommandBuffer,
-    _minDepthBounds: f32,
-    _maxDepthBounds: f32,
+    mut commandBuffer: VkCommandBuffer,
+    minDepthBounds: f32,
+    maxDepthBounds: f32,
 ) {
-    unimplemented!()
+    commandBuffer.set_depth_bounds(minDepthBounds .. maxDepthBounds);
 }
 #[inline]
 pub extern "C" fn gfxCmdSetStencilCompareMask(