7 files changed, 156 insertions, 31 deletions

diff --git a/glow/src/shader/common/triangle.frag b/glow/src/shader/common/triangle.frag
new file mode 100644
index 00000000..e8689f2e
--- /dev/null
+++ b/glow/src/shader/common/triangle.frag
@@ -0,0 +1,18 @@
+#ifdef GL_ES
+#ifdef GL_FRAGMENT_PRECISION_HIGH
+precision highp float;
+#else
+precision mediump float;
+#endif
+#endif
+
+#ifdef HIGHER_THAN_300
+out vec4 fragColor;
+#define gl_FragColor fragColor
+#endif
+
+in vec4 v_Color;
+
+void main() {
+    gl_FragColor = v_Color;
+}
\ No newline at end of file
diff --git a/glow/src/shader/triangle.vert b/glow/src/shader/common/triangle.vert
index 5723436a..d0494a5f 100644
--- a/glow/src/shader/triangle.vert
+++ b/glow/src/shader/common/triangle.vert
@@ -1,13 +1,11 @@
-#version 330
-
 uniform mat4 u_Transform;
 
-layout(location = 0) in vec2 i_Position;
-layout(location = 1) in vec4 i_Color;
+in vec2 i_Position;
+in vec4 i_Color;
 
 out vec4 v_Color;
 
 void main() {
     gl_Position = u_Transform * vec4(i_Position, 0.0, 1.0);
     v_Color = i_Color;
-}
+}
\ No newline at end of file
diff --git a/glow/src/shader/compatibility/quad.frag b/glow/src/shader/compatibility/quad.frag
new file mode 100644
index 00000000..8ea5693d
--- /dev/null
+++ b/glow/src/shader/compatibility/quad.frag
@@ -0,0 +1,67 @@
+#ifdef GL_ES
+#ifdef GL_FRAGMENT_PRECISION_HIGH
+precision highp float;
+#else
+precision mediump float;
+#endif
+#endif
+
+uniform float u_ScreenHeight;
+
+varying vec4 v_Color;
+varying vec4 v_BorderColor;
+varying vec2 v_Pos;
+varying vec2 v_Scale;
+varying float v_BorderRadius;
+varying float v_BorderWidth;
+
+float _distance(vec2 frag_coord, vec2 position, vec2 size, float radius)
+{
+    // TODO: Try SDF approach: https://www.shadertoy.com/view/wd3XRN
+    vec2 inner_size = size - vec2(radius, radius) * 2.0;
+    vec2 top_left = position + vec2(radius, radius);
+    vec2 bottom_right = top_left + inner_size;
+
+    vec2 top_left_distance = top_left - frag_coord;
+    vec2 bottom_right_distance = frag_coord - bottom_right;
+
+    vec2 distance = vec2(
+        max(max(top_left_distance.x, bottom_right_distance.x), 0.0),
+        max(max(top_left_distance.y, bottom_right_distance.y), 0.0)
+    );
+
+    return sqrt(distance.x * distance.x + distance.y * distance.y);
+}
+
+void main() {
+    vec2 fragCoord = vec2(gl_FragCoord.x, u_ScreenHeight - gl_FragCoord.y);
+
+    float internal_border = max(v_BorderRadius - v_BorderWidth, 0.0);
+
+    float internal_distance = _distance(
+        fragCoord,
+        v_Pos + vec2(v_BorderWidth),
+        v_Scale - vec2(v_BorderWidth * 2.0),
+        internal_border
+    );
+
+    float border_mix = smoothstep(
+        max(internal_border - 0.5, 0.0),
+        internal_border + 0.5,
+        internal_distance
+    );
+
+    vec4 mixed_color = mix(v_Color, v_BorderColor, border_mix);
+
+    float d = _distance(
+        fragCoord,
+        v_Pos,
+        v_Scale,
+        v_BorderRadius
+    );
+
+    float radius_alpha =
+        1.0 - smoothstep(max(v_BorderRadius - 0.5, 0.0), v_BorderRadius + 0.5, d);
+
+    gl_FragColor = vec4(mixed_color.xyz, mixed_color.w * radius_alpha);
+}
diff --git a/glow/src/shader/compatibility/quad.vert b/glow/src/shader/compatibility/quad.vert
new file mode 100644
index 00000000..abe70c0e
--- /dev/null
+++ b/glow/src/shader/compatibility/quad.vert
@@ -0,0 +1,44 @@
+uniform mat4 u_Transform;
+uniform float u_Scale;
+
+attribute vec2 i_Pos;
+attribute vec2 i_Scale;
+attribute vec4 i_Color;
+attribute vec4 i_BorderColor;
+attribute float i_BorderRadius;
+attribute float i_BorderWidth;
+attribute vec2 q_Pos;
+
+varying vec4 v_Color;
+varying vec4 v_BorderColor;
+varying vec2 v_Pos;
+varying vec2 v_Scale;
+varying float v_BorderRadius;
+varying float v_BorderWidth;
+
+
+void main() {
+    vec2 p_Pos = i_Pos * u_Scale;
+    vec2 p_Scale = i_Scale  * u_Scale;
+
+    float i_BorderRadius = min(
+        i_BorderRadius,
+        min(i_Scale.x, i_Scale.y) / 2.0
+    );
+
+    mat4 i_Transform = mat4(
+        vec4(p_Scale.x + 1.0, 0.0, 0.0, 0.0),
+        vec4(0.0, p_Scale.y + 1.0, 0.0, 0.0),
+        vec4(0.0, 0.0, 1.0, 0.0),
+        vec4(p_Pos - vec2(0.5, 0.5), 0.0, 1.0)
+    );
+
+    v_Color = i_Color;
+    v_BorderColor = i_BorderColor;
+    v_Pos = p_Pos;
+    v_Scale = p_Scale;
+    v_BorderRadius = i_BorderRadius * u_Scale;
+    v_BorderWidth = i_BorderWidth * u_Scale;
+
+    gl_Position = u_Transform * i_Transform * vec4(q_Pos, 0.0, 1.0);
+}
diff --git a/glow/src/shader/quad.frag b/glow/src/shader/core/quad.frag
index cea36bdc..57e2e8e7 100644
--- a/glow/src/shader/quad.frag
+++ b/glow/src/shader/core/quad.frag
@@ -1,4 +1,15 @@
-#version 330
+#ifdef GL_ES
+#ifdef GL_FRAGMENT_PRECISION_HIGH
+precision highp float;
+#else
+precision mediump float;
+#endif
+#endif
+
+#ifdef HIGHER_THAN_300
+out vec4 fragColor;
+#define gl_FragColor fragColor
+#endif
 
 uniform float u_ScreenHeight;
 
@@ -9,9 +20,7 @@ in vec2 v_Scale;
 in float v_BorderRadius;
 in float v_BorderWidth;
 
-out vec4 o_Color;
-
-float distance(in vec2 frag_coord, in vec2 position, in vec2 size, float radius)
+float fDistance(vec2 frag_coord, vec2 position, 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 +44,10 @@ void main() {
     vec2 fragCoord = vec2(gl_FragCoord.x, u_ScreenHeight - gl_FragCoord.y);
 
     // TODO: Remove branching (?)
-    if(v_BorderWidth > 0) {
+    if(v_BorderWidth > 0.0) {
         float internal_border = max(v_BorderRadius - v_BorderWidth, 0.0);
 
-        float internal_distance = distance(
+        float internal_distance = fDistance(
             fragCoord,
             v_Pos + vec2(v_BorderWidth),
             v_Scale - vec2(v_BorderWidth * 2.0),
@@ -56,7 +65,7 @@ void main() {
         mixed_color = v_Color;
     }
 
-    float d = distance(
+    float d = fDistance(
         fragCoord,
         v_Pos,
         v_Scale,
@@ -66,5 +75,5 @@ void main() {
     float radius_alpha =
         1.0 - smoothstep(max(v_BorderRadius - 0.5, 0.0), v_BorderRadius + 0.5, d);
 
-    o_Color = vec4(mixed_color.xyz, mixed_color.w * radius_alpha);
+    gl_FragColor = vec4(mixed_color.xyz, mixed_color.w * radius_alpha);
 }
diff --git a/glow/src/shader/quad.vert b/glow/src/shader/core/quad.vert
index 82417856..b1fb2365 100644
--- a/glow/src/shader/quad.vert
+++ b/glow/src/shader/core/quad.vert
@@ -1,14 +1,12 @@
-#version 330
-
 uniform mat4 u_Transform;
 uniform float u_Scale;
 
-layout(location = 0) in vec2 i_Pos;
-layout(location = 1) in vec2 i_Scale;
-layout(location = 2) in vec4 i_Color;
-layout(location = 3) in vec4 i_BorderColor;
-layout(location = 4) in float i_BorderRadius;
-layout(location = 5) in float i_BorderWidth;
+in vec2 i_Pos;
+in vec2 i_Scale;
+in vec4 i_Color;
+in vec4 i_BorderColor;
+in float i_BorderRadius;
+in float i_BorderWidth;
 
 out vec4 v_Color;
 out vec4 v_BorderColor;
@@ -17,7 +15,7 @@ out vec2 v_Scale;
 out float v_BorderRadius;
 out float v_BorderWidth;
 
-const vec2 positions[4] = vec2[](
+vec2 positions[4] = vec2[](
     vec2(0.0, 0.0),
     vec2(0.0, 1.0),
     vec2(1.0, 0.0),
diff --git a/glow/src/shader/triangle.frag b/glow/src/shader/triangle.frag
deleted file mode 100644
index d186784a..00000000
--- a/glow/src/shader/triangle.frag
+++ /dev/null
@@ -1,9 +0,0 @@
-#version 330
-
-in vec4 v_Color;
-
-out vec4 o_Color;
-
-void main() {
-    o_Color = v_Color;
-}