1 files changed, 56 insertions, 0 deletions
diff --git a/source/blender/gpu/shaders/compositor/library/gpu_shader_compositor_map_value.glsl b/source/blender/gpu/shaders/compositor/library/gpu_shader_compositor_map_value.glsl
new file mode 100644
index 00000000000..20874b4ef44
--- /dev/null
+++ b/source/blender/gpu/shaders/compositor/library/gpu_shader_compositor_map_value.glsl
@@ -0,0 +1,56 @@
+/* An arbitrary value determined by Blender. */
+#define BLENDER_ZMAX 10000.0
+
+void node_composite_map_range(float value,
+                              float from_min,
+                              float from_max,
+                              float to_min,
+                              float to_max,
+                              const float should_clamp,
+                              out float result)
+{
+  if (abs(from_max - from_min) < 1e-6) {
+    result = 0.0;
+  }
+  else {
+    if (value >= -BLENDER_ZMAX && value <= BLENDER_ZMAX) {
+      result = (value - from_min) / (from_max - from_min);
+      result = to_min + result * (to_max - to_min);
+    }
+    else if (value > BLENDER_ZMAX) {
+      result = to_max;
+    }
+    else {
+      result = to_min;
+    }
+
+    if (should_clamp != 0.0) {
+      if (to_max > to_min) {
+        result = clamp(result, to_min, to_max);
+      }
+      else {
+        result = clamp(result, to_max, to_min);
+      }
+    }
+  }
+}
+
+void node_composite_map_value(float value,
+                              float offset,
+                              float size,
+                              const float use_min,
+                              float min,
+                              const float use_max,
+                              float max,
+                              out float result)
+{
+  result = (value + offset) * size;
+
+  if (use_min != 0.0 && result < min) {
+    result = min;
+  }
+
+  if (use_max != 0.0 && result > max) {
+    result = max;
+  }
+}