vis module extension: background decorator can now use textures (either ImageData or RenderData)

The background decorator can now blend a texture as well as the color gradient. Currently, at fragments where the texture is (0,0,0,0), it will still use the gradient. Also fixes ProcessorDecoratorBackground::addProperties which did not override AbstractProcessorDecorator::addProperties before due to signature mismatch.

core/glsl/tools/background.frag

@@ -22,15 +22,37 @@
 // 
 // ================================================================================================
 
+uniform bool _backgroundHasTexture;
+
 uniform vec4 _backgroundColor1;
 uniform vec4 _backgroundColor2;
 
+uniform sampler2D _backgroundTexture;
+
 void renderBackground(in vec2 texCoords, out vec4 outColor) {
-    outColor = mix(_backgroundColor1, _backgroundColor2, 0.5 * (texCoords.x + texCoords.y));
+    if(_backgroundHasTexture) {
+        outColor = texture(_backgroundTexture, texCoords);
+        if(outColor.a == 0.0)
+            outColor = mix(_backgroundColor1, _backgroundColor2, 0.5 * (texCoords.x + texCoords.y));
+    }
+	else {
+        outColor = mix(_backgroundColor1, _backgroundColor2, 0.5 * (texCoords.x + texCoords.y));
+    }
+
     gl_FragDepth = 1.0;
 }
 
+
 vec4 blendBackground(in vec2 texCoords, in vec4 outColor) {
-    vec4 backgroundColor = mix(_backgroundColor1, _backgroundColor2, 0.5 * (texCoords.x + texCoords.y));
+    vec4 backgroundColor;
+	
+	if(_backgroundHasTexture) {
+		backgroundColor = texture(_backgroundTexture, texCoords);
+        if(dot(backgroundColor,backgroundColor) == 0.0)
+            backgroundColor = mix(_backgroundColor1, _backgroundColor2, 0.5 * (texCoords.x + texCoords.y));
+    }
+	else
+		backgroundColor = mix(_backgroundColor1, _backgroundColor2, 0.5 * (texCoords.x + texCoords.y));
+
     return vec4(mix(backgroundColor.rgb, outColor.rgb, outColor.a), backgroundColor.a);
 }
\ No newline at end of file

core/pipeline/processordecoratorbackground.cpp

@@ -25,14 +25,20 @@
 #include "processordecoratorbackground.h"
 
 #include "cgt/shadermanager.h"
+#include "cgt/textureunit.h"
 #include "core/properties/propertycollection.h"
 
+#include "core/datastructures/imagerepresentationgl.h"
+#include "core/datastructures/renderdata.h"
+
+
 namespace campvis {
 
     ProcessorDecoratorBackground::ProcessorDecoratorBackground()
         : AbstractProcessorDecorator()
         , _backgroundColor1("backgroundColor1", "Background Color 1", cgt::vec4(.9f, .9f, .9f, 1), cgt::vec4(0.f), cgt::vec4(1.f))
         , _backgroundColor2("backgroundColor2", "Background Color 2", cgt::vec4(.6f, .6f, .6f, 1), cgt::vec4(0.f), cgt::vec4(1.f))
+        , _backgroundTexture("backgroundTexture", "Background Texture", "", DataNameProperty::READ)
     {
     }
 
@@ -40,14 +46,43 @@ namespace campvis {
 
     }
 
-    void ProcessorDecoratorBackground::addProperties(HasPropertyCollection* propCollection) {
+    void ProcessorDecoratorBackground::addProperties(AbstractProcessor* propCollection) {
         propCollection->addProperty(_backgroundColor1);
         propCollection->addProperty(_backgroundColor2);
+        propCollection->addProperty(_backgroundTexture);
     }
 
     void ProcessorDecoratorBackground::renderProlog(const DataContainer& dataContainer, cgt::Shader* shader) {
+        ImageRepresentationGL::ScopedRepresentation bg(dataContainer, _backgroundTexture.getValue(), true);
+        ScopedTypedData<RenderData> bgRd(dataContainer, _backgroundTexture.getValue(), true);
+
+        bool hasBackgroundTexture = false;
+
+        if (bg) {
+            hasBackgroundTexture = true;
+            _bgTexUnit = std::make_shared<cgt::TextureUnit>(); // reserve a texture unit
+            bg->bind(shader, *_bgTexUnit, "_backgroundTexture", "_backgroundTextureParams");
+        } 
+        else if (bgRd) {
+            if (auto imageData = bgRd->getColorTexture(0)) {
+                auto imageRep = imageData->getRepresentation<ImageRepresentationGL>();
+                if (imageRep) {
+                    hasBackgroundTexture = true;
+                    _bgTexUnit = std::make_shared<cgt::TextureUnit>(); // reserve a texture unit
+                    imageRep->bind(shader, *_bgTexUnit, "_backgroundTexture", "_backgroundTextureParams");
+                }
+            }
+        }
+
+        shader->setUniform("_backgroundHasTexture", hasBackgroundTexture);
         shader->setUniform("_backgroundColor1", _backgroundColor1.getValue());
         shader->setUniform("_backgroundColor2", _backgroundColor2.getValue());
     }
 
-}
+    void ProcessorDecoratorBackground::renderEpilog(cgt::Shader * shader)
+    {
+        // free the texture unit
+        _bgTexUnit = nullptr;
+    }
+
+}
\ No newline at end of file

core/pipeline/processordecoratorbackground.h

@@ -27,6 +27,11 @@
 
 #include "core/pipeline/abstractprocessordecorator.h"
 #include "core/properties/floatingpointproperty.h"
+#include "core/properties/datanameproperty.h"
+
+namespace cgt {
+    class TextureUnit;
+}
 
 namespace campvis {
 
@@ -36,13 +41,17 @@ namespace campvis {
         virtual ~ProcessorDecoratorBackground();
 
     protected:
-        void addProperties(HasPropertyCollection* propCollection);
+        void addProperties(AbstractProcessor* propCollection) override;
+
+        virtual void renderProlog(const DataContainer& dataContainer, cgt::Shader* shader) override;
 
-        virtual void renderProlog(const DataContainer& dataContainer, cgt::Shader* shader);
+        virtual void renderEpilog(cgt::Shader* shader) override;
 
         Vec4Property _backgroundColor1;
         Vec4Property _backgroundColor2;
+        DataNameProperty _backgroundTexture;
 
+        std::shared_ptr<cgt::TextureUnit> _bgTexUnit;
     };
 
 }

modules/vis/processors/volumeexplorer.cpp

@@ -82,7 +82,6 @@ namespace campvis {
         addProperty(p_enableScribbling, VALID);
 
         addDecorator(new ProcessorDecoratorBackground());
-        decoratePropertyCollection(this);
         
         p_seProperties.addPropertyCollection(*_sliceRenderer);
         _sliceRenderer->p_lqMode.setVisible(false);
@@ -110,6 +109,8 @@ namespace campvis {
         _sliceRenderer->setViewportSizeProperty(&p_smallRenderSize);
         _raycaster.setViewportSizeProperty(&p_largeRenderSize);
 
+        decoratePropertyCollection(this);
+
         addProperty(p_smallRenderSize, VALID);
         addProperty(p_largeRenderSize, VALID);