Refactor bumpmap extensions into a layer

src/osgEarthDrivers/bumpmap/BumpMap.frag.progressive.glsl

@@ -34,37 +34,40 @@ in float oe_bumpmap_range;
 // Entry point for progressive blended bump maps
 void oe_bumpmap_fragment(inout vec4 color)
 {
-	// sample the bump map
-    const float amplitudeDecay = 1.0; // no decay.
-    float maxLOD = float(oe_bumpmap_octaves)+1.0;
-
-    // starter vector:
-    vec3 bump = vec3(0.0);    
-    float scale = 1.0;
-    float amplitude = 1.0;
-    float limit = oe_bumpmap_range;
-    float range = oe_bumpmap_maxRange;
-    float lastRange = oe_bumpmap_maxRange;
-    for(float lod = 1.0; lod < maxLOD; lod += 1.0, scale *= 2.0, amplitude *= amplitudeDecay)
+    if (oe_bumpmap_octaves > 0)
     {
-        float fadeIn = 1.0;
-        if ( range <= limit && limit < oe_bumpmap_maxRange )
-            fadeIn = clamp((lastRange-limit)/(lastRange-range), 0.0, 1.0);
-        bump += (texture(oe_bumpmap_tex, oe_bumpmap_coords*scale).xyz*2.0-1.0)*amplitude*fadeIn;
-        if ( range <= limit )
-            break;
-        lastRange = range;
-        range = oe_bumpmap_maxRange/exp(lod);
-    }
+        // sample the bump map
+        const float amplitudeDecay = 1.0; // no decay.
+        float maxLOD = float(oe_bumpmap_octaves) + 1.0;
+
+        // starter vector:
+        vec3 bump = vec3(0.0);
+        float scale = 1.0;
+        float amplitude = 1.0;
+        float limit = oe_bumpmap_range;
+        float range = oe_bumpmap_maxRange;
+        float lastRange = oe_bumpmap_maxRange;
+        for (float lod = 1.0; lod < maxLOD; lod += 1.0, scale *= 2.0, amplitude *= amplitudeDecay)
+        {
+            float fadeIn = 1.0;
+            if (range <= limit && limit < oe_bumpmap_maxRange)
+                fadeIn = clamp((lastRange - limit) / (lastRange - range), 0.0, 1.0);
+            bump += (texture(oe_bumpmap_tex, oe_bumpmap_coords * scale).xyz * 2.0 - 1.0) * amplitude * fadeIn;
+            if (range <= limit)
+                break;
+            lastRange = range;
+            range = oe_bumpmap_maxRange / exp(lod);
+        }
 
-    // finally, transform into view space and normalize the vector.
-    bump = normalize(oe_bumpmap_normalMatrix*bump);
-
-    // calculate slope from normal:
-    float slope = mix(1.0, 1.0 - dot(oe_UpVectorView, vp_Normal), oe_bumpmap_slopeFactor);
+        // finally, transform into view space and normalize the vector.
+        bump = normalize(oe_bumpmap_normalMatrix * bump);
 
-	// permute the normal with the bump.
-	vp_Normal = normalize(vp_Normal + bump*oe_bumpmap_intensity*slope);
+        // calculate slope from normal:
+        float slope = mix(1.0, 1.0 - dot(oe_UpVectorView, vp_Normal), oe_bumpmap_slopeFactor);
+
+        // permute the normal with the bump.
+        vp_Normal = normalize(vp_Normal + bump * oe_bumpmap_intensity * slope);
+    }
 }
 
 #endif

src/osgEarthDrivers/bumpmap/BumpMap.frag.simple.glsl

@@ -20,20 +20,24 @@ flat in mat3 oe_bumpmap_normalMatrix;
 in vec3 oe_UpVectorView;
 
 uniform sampler2D oe_bumpmap_tex;
-uniform float     oe_bumpmap_intensity;
-uniform float     oe_bumpmap_slopeFactor;
+uniform float oe_bumpmap_intensity;
+uniform float oe_bumpmap_slopeFactor;
+uniform int oe_bumpmap_octaves;
 
 
 void oe_bumpmap_fragment(inout vec4 color)
 {
-	// sample the bump map
-    vec3 bump = oe_bumpmap_normalMatrix * normalize(texture(oe_bumpmap_tex, oe_bumpmap_coords).xyz*2.0-1.0);
-
-    // calculate slope from normal:
-    float slope = clamp( (1.0-dot(oe_UpVectorView, vp_Normal))*oe_bumpmap_slopeFactor, 0.0, 1.0);
-
-	// permute the normal with the bump.
-	vp_Normal = normalize(vp_Normal + bump*oe_bumpmap_intensity*slope);
+    if (oe_bumpmap_octaves > 0)
+    {
+        // sample the bump map
+        vec3 bump = oe_bumpmap_normalMatrix * normalize(texture(oe_bumpmap_tex, oe_bumpmap_coords).xyz * 2.0 - 1.0);
+
+        // calculate slope from normal:
+        float slope = clamp((1.0 - dot(oe_UpVectorView, vp_Normal)) * oe_bumpmap_slopeFactor, 0.0, 1.0);
+
+        // permute the normal with the bump.
+        vp_Normal = normalize(vp_Normal + bump * oe_bumpmap_intensity * slope);
+    }
 }
 
 #endif

src/osgEarthDrivers/bumpmap/BumpMapLayer

@@ -0,0 +1,41 @@
+/* -*-c++-*- */
+/* osgEarth - Geospatial SDK for OpenSceneGraph
+ * Copyright 2020 Pelican Mapping
+ * http://osgearth.org
+ *
+ * osgEarth is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ */
+#pragma once
+
+#include "BumpMapOptions"
+#include "BumpMapTerrainEffect"
+#include <osgEarth/VisibleLayer>
+
+namespace osgEarth
+{
+    class TerrainEngine;
+
+    /**
+        * Layer that installs a bumpmapping terrain effect.
+        */
+    class BumpMapLayer : public VisibleLayer
+    {
+    public:
+        META_Layer(osgEarth, BumpMapLayer, BumpMapOptions, VisibleLayer, bumpmap);
+
+        void prepareForRendering(TerrainEngine* engine) override;
+
+        osg::ref_ptr<BumpMapTerrainEffect> _effect;
+    };
+}

src/osgEarthDrivers/bumpmap/BumpMapLayer.cpp

@@ -0,0 +1,69 @@
+/* -*-c++-*- */
+/* osgEarth - Geospatial SDK for OpenSceneGraph
+ * Copyright 2020 Pelican Mapping
+ * http://osgearth.org
+ *
+ * osgEarth is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ */
+#include "BumpMapLayer"
+#include "BumpMapTerrainEffect"
+
+#include <osgEarth/TerrainEngineNode>
+
+using namespace osgEarth;
+
+#define LC "[BumpMapLayer] "
+
+REGISTER_OSGEARTH_LAYER(bumpmap, BumpMapLayer);
+
+
+void
+BumpMapLayer::prepareForRendering(TerrainEngine* engine)
+{
+    if ( !engine )
+        return;
+
+    osg::ref_ptr<osg::Image> image = options().imageURI()->getImage(getReadOptions());
+    if ( !image.valid() )
+    {
+        OE_WARN << LC << "Failed; unable to load normal map image from "
+            << options().imageURI()->full() << "\n";
+        return;
+    }
+
+    _effect = new BumpMapTerrainEffect();
+
+    _effect->setBumpMapImage(image.get());
+
+    if (options().intensity().isSet())
+        _effect->getIntensityUniform()->set(options().intensity().get());
+
+    if (options().scale().isSet())
+        _effect->getScaleUniform()->set(options().scale().get());
+
+    if (options().octaves().isSet())
+        _effect->setOctaves(options().octaves().get());
+
+    if (options().baseLOD().isSet())
+        _effect->setBaseLOD(options().baseLOD().get());
+
+    engine->addEffect(_effect);
+
+    OE_DEBUG << LC << "Installed.\n";
+
+    onVisibleChanged([&](auto* layer)
+        {
+            _effect->setActive(layer->getVisible());
+        });
+}