Chroma key passthrough

alvr-org · Apr 13, 2024 · 02320ea · 02320ea
1 parent dfadf6c
commit 02320ea
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Showing 3 changed files with 34 additions and 3 deletions.
diff --git a/alvr/client_core/cpp/graphics.cpp b/alvr/client_core/cpp/graphics.cpp
@@ -191,9 +191,22 @@ in lowp vec2 uv;
 in lowp vec4 fragmentColor;
 out lowp vec4 outColor;
 uniform sampler2D Texture0;
-void main()
-{
+
+vec2 RGBToCC(vec4 rgba) {
+    float Y = 0.299 * rgba.r + 0.587 * rgba.g + 0.114 * rgba.b;
+    return vec2((rgba.b - Y) * 0.565, (rgba.r - Y) * 0.713);
+}      
+
+void main() {
+    vec4 keyRGBA = vec4(0.0, 1.0, 0.0, 1.0);    // key color as rgba
+    vec2 keyCC = RGBToCC(keyRGBA);  // the CC part of YCC color model of key color 
+    vec2 range = vec2(0.3, 0.4);     // the smoothstep range
+
     outColor = texture(Texture0, uv);
+    vec2 CC = RGBToCC(outColor);
+
+    float mask = sqrt(pow(keyCC.x - CC.x, 2.0) + pow(keyCC.y - CC.y, 2.0));
+    outColor.a = smoothstep(range.x, range.y, mask);
 }
 )glsl";
 
@@ -683,7 +696,11 @@ void renderEye(
         GL(glBindVertexArray(0));
         GL(glBindTexture(GL_TEXTURE_2D, 0));
     } else {
-        GL(glClear(GL_DEPTH_BUFFER_BIT));
+        GL(glClearColor(0.0f, 0.0f, 0.0f, 0.0f));
+        GL(glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT));
+
+        GL(glEnable(GL_BLEND));
+        GL(glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA));
 
         GL(glBindVertexArray(renderer->Panel.VertexArrayObject));
 

diff --git a/alvr/client_openxr/Cargo.toml b/alvr/client_openxr/Cargo.toml
@@ -103,6 +103,9 @@ required = false
 name = "oculus.software.handtracking"
 required = false
 [[package.metadata.android.uses_feature]]
+name = "com.oculus.feature.PASSTHROUGH"
+required = false
+[[package.metadata.android.uses_feature]]
 name = "com.oculus.software.body_tracking"
 required = false
 [[package.metadata.android.uses_feature]]

diff --git a/alvr/client_openxr/src/lib.rs b/alvr/client_openxr/src/lib.rs
@@ -156,6 +156,7 @@ pub fn entry_point() {
     exts.htc_facial_tracking = available_extensions.htc_facial_tracking;
     exts.htc_vive_focus3_controller_interaction =
         available_extensions.htc_vive_focus3_controller_interaction;
+    exts.fb_passthrough = available_extensions.fb_passthrough;
     #[cfg(target_os = "android")]
     {
         exts.khr_android_create_instance = true;
@@ -203,6 +204,16 @@ pub fn entry_point() {
             session: xr_session.clone(),
         };
 
+        let passthrough = xr_session
+        .create_passthrough(xr::PassthroughFlagsFB::IS_RUNNING_AT_CREATION)
+        .unwrap();
+
+        let _passthrough_layer = xr_session.create_passthrough_layer(
+            &passthrough, 
+            xr::PassthroughFlagsFB::IS_RUNNING_AT_CREATION,
+            xr::PassthroughLayerPurposeFB::RECONSTRUCTION
+        ).unwrap();
+
         let views_config = xr_instance
             .enumerate_view_configuration_views(
                 xr_system,