1 files changed, 86 insertions, 0 deletions
diff --git a/servers/visual/rasterizer_rd/shaders/copy.glsl b/servers/visual/rasterizer_rd/shaders/copy.glsl
new file mode 100644
index 0000000000..cbb9b546a3
--- /dev/null
+++ b/servers/visual/rasterizer_rd/shaders/copy.glsl
@@ -0,0 +1,86 @@
+/* clang-format off */
+[vertex]
+
+#version 450
+
+VERSION_DEFINES
+
+layout(location = 0) out vec2 uv_interp;
+/* clang-format on */
+
+void main() {
+
+	vec2 base_arr[4] = vec2[](vec2(0.0, 0.0), vec2(0.0, 1.0), vec2(1.0, 1.0), vec2(1.0, 0.0));
+	uv_interp = base_arr[gl_VertexIndex];
+
+	gl_Position = vec4(uv_interp * 2.0 - 1.0, 0.0, 1.0);
+}
+
+/* clang-format off */
+[fragment]
+
+#version 450
+
+VERSION_DEFINES
+
+layout(location = 0) in vec2 uv_interp;
+/* clang-format on */
+
+#ifdef MODE_CUBE_TO_DP
+
+layout(set = 0, binding = 0) uniform samplerCube source_cube;
+
+layout(push_constant, binding = 0, std430) uniform Params {
+	float bias;
+	float z_far;
+	float z_near;
+	bool z_flip;
+}
+params;
+
+layout(location = 0) out float depth_buffer;
+
+#endif
+
+void main() {
+
+#ifdef MODE_CUBE_TO_DP
+
+	vec3 normal = vec3(uv_interp * 2.0 - 1.0, 0.0);
+
+	normal.z = 0.5 - 0.5 * ((normal.x * normal.x) + (normal.y * normal.y));
+	normal = normalize(normal);
+
+	normal.y = -normal.y; //needs to be flipped to match projection matrix
+	if (!params.z_flip) {
+		normal.z = -normal.z;
+	}
+
+	float depth = texture(source_cube, normal).r;
+
+	// absolute values for direction cosines, bigger value equals closer to basis axis
+	vec3 unorm = abs(normal);
+
+	if ((unorm.x >= unorm.y) && (unorm.x >= unorm.z)) {
+		// x code
+		unorm = normal.x > 0.0 ? vec3(1.0, 0.0, 0.0) : vec3(-1.0, 0.0, 0.0);
+	} else if ((unorm.y > unorm.x) && (unorm.y >= unorm.z)) {
+		// y code
+		unorm = normal.y > 0.0 ? vec3(0.0, 1.0, 0.0) : vec3(0.0, -1.0, 0.0);
+	} else if ((unorm.z > unorm.x) && (unorm.z > unorm.y)) {
+		// z code
+		unorm = normal.z > 0.0 ? vec3(0.0, 0.0, 1.0) : vec3(0.0, 0.0, -1.0);
+	} else {
+		// oh-no we messed up code
+		// has to be
+		unorm = vec3(1.0, 0.0, 0.0);
+	}
+
+	float depth_fix = 1.0 / dot(normal, unorm);
+
+	depth = 2.0 * depth - 1.0;
+	float linear_depth = 2.0 * params.z_near * params.z_far / (params.z_far + params.z_near - depth * (params.z_far - params.z_near));
+	depth_buffer = (linear_depth * depth_fix + params.bias) / params.z_far;
+
+#endif
+}