diff --git a/data/layout.xml b/data/layout.xml
index 35d5245..3bad08e 100644
--- a/data/layout.xml
+++ b/data/layout.xml
@@ -298,6 +298,7 @@
             <node height="20" justify="center"><text text="L-Yaw" font-face="arial" font-size="11"/></node>
             <node height="20" justify="center"><text text="L-Pitch" font-face="arial" font-size="11"/></node>
             <node height="20" justify="center"><text text="Ambient" font-face="arial" font-size="11"/></node>
+            <node height="20" justify="center"><text text="Radius" font-face="arial" font-size="11"/></node>
             <node height="30" justify="center" margin="5 0 0 0"><text text="Samples" font-face="arial" font-size="11"/></node>
             <node height="30" justify="center" margin="5 0 0 0"><text text="Tex Res." font-face="arial" font-size="11"/></node>
           </node>
@@ -318,6 +319,7 @@
             <node height="20" pad="1" width="100%"><slider-h id="grid-heightmap-lyaw" value="0.5"/></node>
             <node height="20" pad="1" width="100%"><slider-h id="grid-heightmap-lpitch" value="0.1"/></node>
             <node height="20" pad="1" width="100%"><slider-h id="grid-heightmap-ambient" value="0.0"/></node>
+            <node height="20" pad="1" width="100%"><slider-h id="grid-heightmap-radius" value="0.25"/></node>
             <node height="30" pad="1" width="100%" dir="row" margin="5 0 0 0">
               <combobox id="grid-heightmap-samples" width="100%" height="30" combo-list="1,4,8,16,32,64,128" default="2"/>
             </node>
diff --git a/src/node_panel_grid.cpp b/src/node_panel_grid.cpp
index 2da1bff..e2f4438 100644
--- a/src/node_panel_grid.cpp
+++ b/src/node_panel_grid.cpp
@@ -39,6 +39,7 @@ void NodePanelGrid::init_controls()
     m_hm_lyaw = find<NodeSliderH>("grid-heightmap-lyaw");
     m_hm_lpitch = find<NodeSliderH>("grid-heightmap-lpitch");
     m_hm_ambient = find<NodeSliderH>("grid-heightmap-ambient");
+    m_hm_radius = find<NodeSliderH>("grid-heightmap-radius");
     m_hm_shading = find<NodeComboBox>("grid-heightmap-shading");
     m_hm_texres = find<NodeComboBox>("grid-heightmap-texres");
     m_hm_samples = find<NodeComboBox>("grid-heightmap-samples");
@@ -141,7 +142,7 @@ void NodePanelGrid::init_controls()
     };
     m_hm_texres->on_select = [this](Node*, int index) {
         int texres = get_texres();
-        if (texres != m_texture.size().x)
+        if (texres == m_texture.size().x)
             return;
 
         // get the texture data and resize it
@@ -177,6 +178,11 @@ int NodePanelGrid::get_texres() const
     return atoi(m_hm_texres->m_items[m_hm_texres->m_current_index].c_str());
 }
 
+float NodePanelGrid::get_radius() const
+{
+    return m_hm_radius->get_value() * 0.5f + 0.01f;
+}
+
 float NodePanelGrid::get_ambient() const
 {
     return glm::pow(m_hm_ambient->get_value(), 3);
@@ -365,6 +371,7 @@ void NodePanelGrid::bake_uvs()
 
     auto data_out = std::make_unique<uint8_t[]>(fb.getWidth() * fb.getHeight() * 4);
     const auto samples = get_samples();
+    const auto radius = get_radius();
     std::thread worker([&]
     {
         __block float* d_pos = data_pos.get();
@@ -395,7 +402,7 @@ void NodePanelGrid::bake_uvs()
                 int hit = 0;
                 for (int s = 0; s < samples; s++)
                 {
-                    auto dir = glm::normalize(light_dir + glm::sphericalRand(.5f));
+                    auto dir = glm::normalize(light_dir + glm::sphericalRand(radius));
 
                     nanort::Ray<float> ray;
                     ray.org[0] = pos.x;// + nor.x * 0.005;
diff --git a/src/node_panel_grid.h b/src/node_panel_grid.h
index 73f5b3b..6a11d95 100644
--- a/src/node_panel_grid.h
+++ b/src/node_panel_grid.h
@@ -51,6 +51,7 @@ public:
     NodeSliderH* m_hm_lyaw;
     NodeSliderH* m_hm_lpitch;
     NodeSliderH* m_hm_ambient;
+    NodeSliderH* m_hm_radius;
     NodeComboBox* m_hm_texres;
     NodeComboBox* m_hm_samples;
     NodeButton* m_render;
@@ -75,6 +76,7 @@ public:
     void init_controls();
     int get_samples() const;
     int get_texres() const;
+    float get_radius() const;
     float get_ambient() const;
     float get_thickness() const;
     float get_resolution() const;