1 files changed, 47 insertions, 0 deletions
diff --git a/source/blender/gpu/shaders/gpu_shader_image_overlays_stereo_merge_frag.glsl b/source/blender/gpu/shaders/gpu_shader_image_overlays_stereo_merge_frag.glsl
new file mode 100644
index 00000000000..c6e9860d940
--- /dev/null
+++ b/source/blender/gpu/shaders/gpu_shader_image_overlays_stereo_merge_frag.glsl
@@ -0,0 +1,47 @@
+#define S3D_DISPLAY_ANAGLYPH 0
+#define S3D_DISPLAY_INTERLACE 1
+
+#define S3D_INTERLACE_ROW 0
+#define S3D_INTERLACE_COLUMN 1
+#define S3D_INTERLACE_CHECKERBOARD 2
+
+/* Composite stereo textures */
+
+uniform sampler2D imageTexture;
+uniform sampler2D overlayTexture;
+
+uniform int stereoDisplaySettings;
+
+#define stereo_display_mode (stereoDisplaySettings & ((1 << 3) - 1))
+#define stereo_interlace_mode ((stereoDisplaySettings >> 3) & ((1 << 3) - 1))
+#define stereo_interlace_swap bool(stereoDisplaySettings >> 6)
+
+layout(location = 0) out vec4 imageColor;
+layout(location = 1) out vec4 overlayColor;
+
+bool interlace(ivec2 texel)
+{
+  int interlace_mode = stereo_interlace_mode;
+  if (interlace_mode == S3D_INTERLACE_CHECKERBOARD) {
+    return ((texel.x + texel.y) & 1) != 0;
+  }
+  else if (interlace_mode == S3D_INTERLACE_ROW) {
+    return (texel.y & 1) != 0;
+  }
+  else if (interlace_mode == S3D_INTERLACE_COLUMN) {
+    return (texel.x & 1) != 0;
+  }
+}
+
+void main()
+{
+  ivec2 texel = ivec2(gl_FragCoord.xy);
+
+  if (stereo_display_mode == S3D_DISPLAY_INTERLACE &&
+      (interlace(texel) == stereo_interlace_swap)) {
+    discard;
+  }
+
+  imageColor = texelFetch(imageTexture, texel, 0);
+  overlayColor = texelFetch(overlayTexture, texel, 0);
+}