My attempt to make it work

Cargo.toml

@@ -13,6 +13,7 @@ categories = ["gui"]
 
 [features]
 default = ["wgpu", "default_system_font"]
+#default = ["wgpu", "default_system_font", "glow", "glow_canvas"]
 # Enables the `iced_wgpu` renderer
 wgpu = ["iced_wgpu"]
 # Enables the `Image` widget
@@ -90,3 +91,6 @@ iced_web = { version = "0.2", path = "web" }
 [package.metadata.docs.rs]
 rustdoc-args = ["--cfg", "docsrs"]
 features = ["image", "svg", "canvas"]
+
+[patch.crates-io]
+glow_glyph = { path = '../glow_glyph' }

examples/counter/Cargo.toml

@@ -6,4 +6,4 @@ edition = "2018"
 publish = false
 
 [dependencies]
-iced = { path = "../.." }
+iced = { path = "../..", features = ["glow"] }

examples/stopwatch/Cargo.toml

@@ -6,4 +6,4 @@ edition = "2018"
 publish = false
 
 [dependencies]
-iced = { path = "../..", features = ["tokio"] }
+iced = { path = "../..", features = ["tokio", "glow"] }

glow/src/shader/quad.frag

@@ -1,4 +1,5 @@
-#version 330
+#version 300 es
+precision highp float;
 
 uniform float u_ScreenHeight;
 
@@ -11,7 +12,7 @@ in float v_BorderWidth;
 
 out vec4 o_Color;
 
-float distance(in vec2 frag_coord, in vec2 position, in vec2 size, float radius)
+float distance1(in vec2 frag_coord, in vec2 position, in vec2 size, float radius)
 {
     // TODO: Try SDF approach: https://www.shadertoy.com/view/wd3XRN
     vec2 inner_size = size - vec2(radius, radius) * 2.0;
@@ -35,10 +36,10 @@ void main() {
     vec2 fragCoord = vec2(gl_FragCoord.x, u_ScreenHeight - gl_FragCoord.y);
 
     // TODO: Remove branching (?)
-    if(v_BorderWidth > 0) {
+    if(v_BorderWidth > 0.) {
         float internal_border = max(v_BorderRadius - v_BorderWidth, 0.0);
 
-        float internal_distance = distance(
+        float internal_distance = distance1(
             fragCoord,
             v_Pos + vec2(v_BorderWidth),
             v_Scale - vec2(v_BorderWidth * 2.0),
@@ -56,7 +57,7 @@ void main() {
         mixed_color = v_Color;
     }
 
-    float d = distance(
+    float d = distance1(
         fragCoord,
         v_Pos,
         v_Scale,

glow/src/shader/quad.vert

@@ -1,4 +1,5 @@
-#version 330
+#version 300 es
+precision highp float;
 
 uniform mat4 u_Transform;
 uniform float u_Scale;

glow/src/shader/triangle.frag

@@ -1,4 +1,5 @@
-#version 330
+#version 300 es
+precision highp float;
 
 in vec4 v_Color;
 

glow/src/shader/triangle.vert

@@ -1,4 +1,5 @@
-#version 330
+#version 300 es
+precision highp float;
 
 uniform mat4 u_Transform;
 

graphics/Cargo.toml

@@ -29,7 +29,7 @@ version = "0.15"
 optional = true
 
 [dependencies.font-kit]
-version = "0.6"
+version = "0.9"
 optional = true
 
 [package.metadata.docs.rs]

log

@@ -0,0 +1,5 @@
+    Finished dev [unoptimized + debuginfo] target(s) in 0.52s
+     Running `target/debug/stopwatch`
+thread 'main' panicked at '0:1(10): error: GLSL 3.30 is not supported. Supported versions are: 1.10, 1.20, 1.00 ES, and 3.00 ES
+', /home/pi/.cargo/registry/src/git.luolix.top-1ecc6299db9ec823/glow_glyph-0.2.0/src/pipeline.rs:287:13
+note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

wgpu/Cargo.toml

@@ -26,6 +26,10 @@ guillotiere = "0.5"
 # resolved
 gfx-memory = "=0.1.1"
 
+[dependencies.wgpu-native]
+version = "0.5"
+features = ["vulkan-portability"]
+
 [dependencies.iced_native]
 version = "0.2"
 path = "../native"