Preparation for merge. Added check to IpsviRaycaster whether OpenGL 4.4 is...

Preparation for merge. Added check to IpsviRaycaster whether OpenGL 4.4 is supported to avoid crashes if this is not the case.

modules/vis/processors/ipsviraycaster.cpp

@@ -45,6 +45,7 @@ namespace campvis {
         , p_icTextureSize("IcTextureSize", "Illumination Cache Texture Size", cgt::ivec2(512), cgt::ivec2(32), cgt::ivec2(2048))
         , p_shadowIntensity("ShadowIntensity", "Shadow Intensity", .75f, 0.f, 1.f)
         , _vhm(nullptr)
+        , _gl44Supported(false)
     {
         _icTextures[0] = nullptr;
         _icTextures[1] = nullptr;
@@ -65,13 +66,25 @@ namespace campvis {
     }
 
     void IpsviRaycaster::init() {
-        RaycastingProcessor::init();
+        // get supported OpenGL version
+        // if OpenGL 4.4 is not supported, abort the initialization, since compiling the shader will fail.
+        _gl44Supported = (GpuCaps.getGlVersion() >= cgt::GpuCapabilities::GlVersion::CGT_GL_VERSION_4_4);
+        _gl44Supported &= (GpuCaps.getShaderVersion() >= cgt::GpuCapabilities::GlVersion::SHADER_VERSION_440);
+        if (! _gl44Supported) {
+            LERROR("This system does not support OpenGL 4.4, which is required for the IpsviRaycaster. Raycaster deactivated.");
+            return;
+        }
 
+        RaycastingProcessor::init();
         _vhm = new VoxelHierarchyMapper();
         invalidate(INVALID_BBV | INVALID_IC_TEXTURES);
     }
 
     void IpsviRaycaster::deinit() {
+        // nothing to deinitialize, if this processor has never been initialized.
+        if (!_gl44Supported)
+            return;
+
         delete _vhm;
         delete _icTextures[0];
         delete _icTextures[1];
@@ -79,6 +92,13 @@ namespace campvis {
         RaycastingProcessor::deinit();
     }
 
+    void IpsviRaycaster::updateResult(DataContainer& data) {
+        if (!_gl44Supported)
+            return;
+
+        RaycastingProcessor::updateResult(data);
+    }
+
     void IpsviRaycaster::processImpl(DataContainer& data, ImageRepresentationGL::ScopedRepresentation& image) {
         // (re)create Illumination Cache (IC) textures if needed
         if (getInvalidationLevel() & INVALID_IC_TEXTURES) {
@@ -174,7 +194,7 @@ namespace campvis {
         corners[6] = cgt::vec3(worldBounds.getURB().x, worldBounds.getURB().y, worldBounds.getLLF().z);
         corners[7] = cgt::vec3(worldBounds.getURB().x, worldBounds.getURB().y, worldBounds.getURB().z);
 
-        for (auto i = 0; i < corners.size(); ++i) {
+        for (size_t i = 0; i < corners.size(); ++i) {
             const cgt::vec3 diag = corners[i];
             const float distance = std::abs(cgt::dot(diag, icNormal));
             const cgt::vec3 projected = diag - (-distance * icNormal);

modules/vis/processors/ipsviraycaster.h

@@ -92,6 +92,8 @@ namespace campvis {
         FloatProperty p_shadowIntensity;            ///< Intensity of the shadowing effect
     
     protected:
+        /// \see RaycastingProcessor::updateResult()
+        virtual void updateResult(DataContainer& data) override;
         /// \see RaycastingProcessor::processImpl()
         virtual void processImpl(DataContainer& data, ImageRepresentationGL::ScopedRepresentation& image);
 
@@ -100,6 +102,7 @@ namespace campvis {
 
         VoxelHierarchyMapper* _vhm;     ///< for optimizing entry/exit points
         cgt::Texture* _icTextures[2];   ///< Illumination cache textures
+        bool _gl44Supported;            ///< Flag whether OpenGL 4.4 is supported.
 
         static const std::string loggerCat_;
     };