Each mesh now has it's own transform matrix applied, so that our example framework can support breaking a volume into regions.

examples/Basic/OpenGLWidget.cpp

@@ -127,17 +127,14 @@ void OpenGLWidget::paintGL()
 	//Clear the screen
 	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
-	QMatrix4x4 modelToWorldMatrix{};
-	//modelToWorldMatrix.rotate(m_xRotation, 0, 1, 0); //rotate around y-axis
-	//modelToWorldMatrix.rotate(m_yRotation, 1, 0, 0); //rotate around x-axis
-	//modelToWorldMatrix.translate(-32, -32, -32); //centre the model on the origin
-
 	shader.bind();
 
-	shader.setUniformValue("modelToWorldMatrix", modelToWorldMatrix); //Update to the latest camera matrix
-
 	for (OpenGLMeshData meshData : mMeshData)
 	{
+		QMatrix4x4 modelToWorldMatrix{};
+		modelToWorldMatrix.translate(meshData.translation.getX(), meshData.translation.getY(), meshData.translation.getZ()); // Centre the model on the origin
+		shader.setUniformValue("modelToWorldMatrix", modelToWorldMatrix); // Update to the latest camera matrix
+
 		glBindVertexArray(meshData.vertexArrayObject);
 
 		glDrawElements(GL_TRIANGLES, meshData.noOfIndices, GL_UNSIGNED_INT, 0);

examples/Basic/OpenGLWidget.h

@@ -37,6 +37,7 @@ struct OpenGLMeshData
 	GLuint indexBuffer;
 	GLuint vertexBuffer;
 	GLuint vertexArrayObject;
+	PolyVox::Vector3DInt32 translation;
 };
 
 class OpenGLWidget : public QGLWidget
@@ -49,43 +50,13 @@ public:
 	void mouseMoveEvent(QMouseEvent* event);
 	void mousePressEvent(QMouseEvent* event);
 
-	// Convert a SurfaceMesh to OpenGL index/vertex buffers
-	template <typename MeshType>
-	void addMesh(const MeshType& surfaceMesh);
-
 	// The viewable region can be adjusted so that this example framework can be use for different volume sizes.
 	void setViewableRegion(PolyVox::Region viewableRegion);
 
-protected:
+	// Convert a SurfaceMesh to OpenGL index/vertex buffers. Inlined because it's templatised.
-	
+	template <typename MeshType>
-
+	void addMesh(const MeshType& surfaceMesh)
-	// Qt OpenGL functions
+	{
-	void initializeGL();
-	void resizeGL(int w, int h);
-	void paintGL();
-
-private:
-
-	void setupWorldToCameraMatrix();
-
-	// Index/vertex buffer data
-	std::vector<OpenGLMeshData> mMeshData;
-	
-	QGLShaderProgram shader;
-
-	// Mouse data
-	QPoint m_LastFrameMousePos;
-	QPoint m_CurrentMousePos;
-
-	// Camera setup
-	PolyVox::Region m_viewableRegion;
-	int m_xRotation;
-	int m_yRotation;
-};
-
-template <typename MeshType>
-void OpenGLWidget::addMesh(const MeshType& surfaceMesh)
-{
 		//Convienient access to the vertices and indices
 		const auto& vecIndices = surfaceMesh.getIndices();
 		const auto& vecVertices = surfaceMesh.getVertices();
@@ -116,7 +87,36 @@ void OpenGLWidget::addMesh(const MeshType& surfaceMesh)
 
 		meshData.noOfIndices = vecIndices.size(); //Save this for the call to glDrawElements later
 
+		meshData.translation = surfaceMesh.m_Region.getLowerCorner();
+
 		mMeshData.push_back(meshData);
-}
+	}
+
+protected:
+	
+
+	// Qt OpenGL functions
+	void initializeGL();
+	void resizeGL(int w, int h);
+	void paintGL();
+
+private:
+
+	void setupWorldToCameraMatrix();
+
+	// Index/vertex buffer data
+	std::vector<OpenGLMeshData> mMeshData;
+	
+	QGLShaderProgram shader;
+
+	// Mouse data
+	QPoint m_LastFrameMousePos;
+	QPoint m_CurrentMousePos;
+
+	// Camera setup
+	PolyVox::Region m_viewableRegion;
+	int m_xRotation;
+	int m_yRotation;
+};
 
 #endif //__BasicExample_OpenGLWidget_H__

examples/Basic/main.cpp

@@ -78,16 +78,16 @@ int main(int argc, char *argv[])
 	createSphereInVolume(volData, 30);
 
 	// Extract the surface for the specified region of the volume. Uncomment the line for the kind of surface extraction you want to see.
-	auto mesh = extractCubicMesh(&volData, volData.getEnclosingRegion());
+	//auto mesh = extractCubicMesh(&volData, volData.getEnclosingRegion());
 	//auto mesh = extractMarchingCubesMesh(&volData, volData.getEnclosingRegion());
 
-	//auto mesh = extractCubicMesh(&volData, PolyVox::Region(Vector3DInt32(0, 0, 0), Vector3DInt32(31, 31, 31)));
+	auto mesh = extractCubicMesh(&volData, PolyVox::Region(Vector3DInt32(0, 0, 0), Vector3DInt32(31, 31, 31)));
-	//auto mesh2 = extractCubicMesh(&volData, PolyVox::Region(Vector3DInt32(32, 32, 32), Vector3DInt32(63, 63, 63)));
+	auto mesh2 = extractCubicMesh(&volData, PolyVox::Region(Vector3DInt32(32, 32, 32), Vector3DInt32(63, 63, 63)));
 
 	//Pass the surface to the OpenGL window
 	openGLWidget.addMesh(mesh);
+	openGLWidget.addMesh(mesh2);
 	openGLWidget.setViewableRegion(volData.getEnclosingRegion());
-	//openGLWidget.addMesh(mesh2);
 
 	//Run the message pump.
 	return app.exec();