1 files changed, 95 insertions, 0 deletions
diff --git a/servers/rendering/renderer_rd/shaders/blit.glsl b/servers/rendering/renderer_rd/shaders/blit.glsl
new file mode 100644
index 0000000000..967da1e6e4
--- /dev/null
+++ b/servers/rendering/renderer_rd/shaders/blit.glsl
@@ -0,0 +1,95 @@
+#[vertex]
+
+#version 450
+
+#VERSION_DEFINES
+
+layout(push_constant, binding = 0, std140) uniform Pos {
+	vec4 dst_rect;
+
+	vec2 eye_center;
+	float k1;
+	float k2;
+
+	float upscale;
+	float aspect_ratio;
+	uint layer;
+	uint pad1;
+}
+data;
+
+layout(location = 0) out vec2 uv;
+
+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 = base_arr[gl_VertexIndex];
+	vec2 vtx = data.dst_rect.xy + uv * data.dst_rect.zw;
+	gl_Position = vec4(vtx * 2.0 - 1.0, 0.0, 1.0);
+}
+
+#[fragment]
+
+#version 450
+
+#VERSION_DEFINES
+
+layout(push_constant, binding = 0, std140) uniform Pos {
+	vec4 dst_rect;
+
+	vec2 eye_center;
+	float k1;
+	float k2;
+
+	float upscale;
+	float aspect_ratio;
+	uint layer;
+	uint pad1;
+}
+data;
+
+layout(location = 0) in vec2 uv;
+
+layout(location = 0) out vec4 color;
+
+#ifdef USE_LAYER
+layout(binding = 0) uniform sampler2DArray src_rt;
+#else
+layout(binding = 0) uniform sampler2D src_rt;
+#endif
+
+void main() {
+#ifdef APPLY_LENS_DISTORTION
+	vec2 coords = uv * 2.0 - 1.0;
+	vec2 offset = coords - data.eye_center;
+
+	// take aspect ratio into account
+	offset.y /= data.aspect_ratio;
+
+	// distort
+	vec2 offset_sq = offset * offset;
+	float radius_sq = offset_sq.x + offset_sq.y;
+	float radius_s4 = radius_sq * radius_sq;
+	float distortion_scale = 1.0 + (data.k1 * radius_sq) + (data.k2 * radius_s4);
+	offset *= distortion_scale;
+
+	// reapply aspect ratio
+	offset.y *= data.aspect_ratio;
+
+	// add our eye center back in
+	coords = offset + data.eye_center;
+	coords /= data.upscale;
+
+	// and check our color
+	if (coords.x < -1.0 || coords.y < -1.0 || coords.x > 1.0 || coords.y > 1.0) {
+		color = vec4(0.0, 0.0, 0.0, 1.0);
+	} else {
+		// layer is always used here
+		coords = (coords + vec2(1.0)) / vec2(2.0);
+		color = texture(src_rt, vec3(coords, data.layer));
+	}
+#elif defined(USE_LAYER)
+	color = texture(src_rt, vec3(uv, data.layer));
+#else
+	color = texture(src_rt, uv);
+#endif
+}