Rex: update so you can set the terrain color and other uniform-based …

…terrain options dynamically at runtime, and add a color slider to the imgui panel; also clean up some old debugging code in the normal map shaders

src/osgEarthDrivers/engine_rex/RexEngine.NormalMap.GL4.glsl

@@ -30,8 +30,6 @@ void oe_rex_normalMapVS(inout vec4 unused)
 #pragma vp_function oe_rex_normalMapFS, fragment_coloring, 0.1
 
 #pragma import_defines(OE_TERRAIN_RENDER_NORMAL_MAP)
-#pragma import_defines(OE_DEBUG_NORMALS)
-#pragma import_defines(OE_DEBUG_CURVATURE)
 
 in vec3 vp_Normal;
 in vec3 oe_UpVectorView;
@@ -61,17 +59,4 @@ void oe_rex_normalMapFS(inout vec4 color)
         vp_Normal = normalize( oe_normalMapTBN*N.xyz );
     }
 #endif
-
-#ifdef OE_DEBUG_CURVATURE
-    // visualize curvature quantized:
-    color.rgba = vec4(0, 0, 0, 1);
-    float curvature = N.w;
-    if (curvature > 0.0) color.r = curvature;
-    if (curvature < 0.0) color.g = -curvature;
-#endif
-
-#ifdef OE_DEBUG_NORMALS
-    // visualize normals:
-    color.rgb = (N.xyz + 1.0)*0.5;
-#endif
 }

src/osgEarthDrivers/engine_rex/RexEngine.NormalMap.glsl

@@ -45,8 +45,6 @@ void oe_rex_normalMapVS(inout vec4 unused)
 #pragma vp_order      0.1
 
 #pragma import_defines(OE_TERRAIN_RENDER_NORMAL_MAP)
-#pragma import_defines(OE_DEBUG_NORMALS)
-#pragma import_defines(OE_DEBUG_CURVATURE)
 
 // import terrain SDK
 vec4 oe_terrain_getNormalAndCurvature(in vec2);
@@ -72,17 +70,4 @@ void oe_rex_normalMapFS(inout vec4 color)
     vec3 tangent = normalize(cross(oe_normal_binormal, oe_UpVectorView));
     oe_normalMapTBN = mat3(tangent, oe_normal_binormal, oe_UpVectorView);
     vp_Normal = normalize(oe_normalMapTBN*N.xyz);
-
-#ifdef OE_DEBUG_CURVATURE
-    // visualize curvature quantized:
-    color.rgba = vec4(0, 0, 0, 1);
-    float curvature = N.w;
-    if (curvature > 0.0) color.r = curvature;
-    if (curvature < 0.0) color.g = -curvature;
-#endif
-
-#ifdef OE_DEBUG_NORMALS
-    // visualize normals:
-    color.rgb = (N.xyz + 1.0)*0.5;
-#endif
 }

src/osgEarthDrivers/engine_rex/RexTerrainEngineNode.cpp

@@ -276,12 +276,6 @@ RexTerrainEngineNode::onSetMap()
         _morphTerrainSupported = false;
     }
 
-    // Check for normals debugging.
-    if (::getenv("OSGEARTH_DEBUG_NORMALS"))
-        getOrCreateStateSet()->setDefine("OE_DEBUG_NORMALS");
-    else
-        if (getStateSet()) getStateSet()->removeDefine("OE_DEBUG_NORMALS");
-
     // check for normal map generation (required for lighting).
     _requirements.normalTextures = (options.getUseNormalMaps() == true);
 
@@ -732,11 +726,7 @@ RexTerrainEngineNode::dirtyTerrainOptions()
 
     jobs::get_pool(ARENA_LOAD_TILE)->set_concurrency(options.getConcurrency());
 
-    getSurfaceStateSet()->getOrCreateUniform(
-        "oe_terrain_tess", osg::Uniform::FLOAT)->set(options.getTessellationLevel());
-
-    getSurfaceStateSet()->getOrCreateUniform(
-        "oe_terrain_tess_range", osg::Uniform::FLOAT)->set(options.getTessellationRange());
+    updateState();
 }
 
 void

src/osgEarthDrivers/engine_rex/TileNode.cpp

@@ -347,22 +347,26 @@ TileNode::shouldSubDivide(TerrainCuller* culler, const SelectionInfo& selectionI
         // allowable on-screen tile size in pixels.
         if (_context->options().getLODMethod() == LODMethod::SCREEN_SPACE)
         {
-            float tileSizeInPixels = -1.0;
+            // assume the imagery of a tile to be this dimension (pixels). If so, once the
+            // size of tile geometry on screen exceeds that, it's time to subdivide.
+            float tileImagerySize = _context->options().getTilePixelSize();
+
+            float tileGeometrySizeInPixels = -1.0;
 
             if (context->getEngine()->getComputeTilePixelSizeCallback())
             {
-                tileSizeInPixels = (context->getEngine()->getComputeTilePixelSizeCallback())(this, *culler->_cv);
+                tileGeometrySizeInPixels = (context->getEngine()->getComputeTilePixelSizeCallback())(this, *culler->_cv);
             }
 
-            if (tileSizeInPixels <= 0.0)
+            if (tileGeometrySizeInPixels <= 0.0)
             {
-                tileSizeInPixels = _surface->getPixelSizeOnScreen(culler);
+                tileGeometrySizeInPixels = _surface->getPixelSizeOnScreen(culler);
             }
 
-            float effectivePixelSize =
-                _context->options().getTilePixelSize() + _context->options().getScreenSpaceError();
+            // SSE is the amount of error we are willing to tolerate in the screen space size
+            float pixelSizeThreshold = tileImagerySize + _context->options().getScreenSpaceError();
 
-            return (tileSizeInPixels > effectivePixelSize);
+            return (tileGeometrySizeInPixels > pixelSizeThreshold);
         }
 
         // In DISTANCE-TO-EYE mode, use the visibility ranges precomputed in the SelectionInfo.

src/osgEarthImGui/TerrainGUI

@@ -138,6 +138,13 @@ namespace osgEarth
                         }
                     }
 
+                    Color color = options.getColor();
+                    if (ImGuiLTable::ColorEdit3("Background", color.ptr()))
+                    {
+                        options.setColor(color);
+                        engine->dirtyTerrainOptions();
+                    }
+
                     if (GLUtils::useNVGL())
                     {
                         unsigned maxTex = options.getMaxTextureSize();