Playing with picking

RenderingManager.cpp

@@ -21,6 +21,7 @@
 #include <GLFW/glfw3native.h>
 
 #include <glm/ext/matrix_transform.hpp> // glm::translate, glm::rotate, glm::scale
+#include <glm/ext/matrix_projection.hpp> // glm::unproject
 #include <glm/ext/matrix_clip_space.hpp> // glm::perspective
 
 // Include GStreamer
@@ -318,6 +319,18 @@ glm::mat4 Rendering::Projection()
     return projection * scale;
 }
 
+
+glm::vec3 Rendering::unProject(glm::vec2 screen_coordinate, glm::mat4 modelview)
+{
+    glm::vec3 point;
+    glm::vec3 coordinates = glm::vec3( glm::vec2(screen_coordinate), 0.f);
+    glm::vec4 viewport = glm::vec4( 0.f, 0.f, main_window_attributes_.viewport.x, main_window_attributes_.viewport.y);
+
+    point = glm::unProject(coordinates, modelview, Projection(), viewport);
+
+    return point;
+}
+
 float Rendering::Width() { return main_window_attributes_.viewport.x; }
 float Rendering::Height() { return main_window_attributes_.viewport.y; }
 

RenderingManager.h

@@ -75,6 +75,8 @@ public:
 
     // get projection matrix (for sharers) => Views
     glm::mat4 Projection();
+    // unproject from window coordinate
+    glm::vec3 unProject(glm::vec2 screen_coordinate, glm::mat4 modelview);
 
     // for opengl pipeline in gstreamer
     void LinkPipeline( GstPipeline *pipeline );

UserInterfaceManager.cpp

@@ -19,6 +19,11 @@
 // multiplatform
 #include <tinyfiledialogs.h>
 
+#include <glm/glm.hpp>
+#include <glm/ext/vector_float3.hpp>
+#include <glm/ext/matrix_float4x4.hpp>
+#include <glm/ext/matrix_transform.hpp>
+
 // generic image loader
 #define STB_IMAGE_IMPLEMENTATION
 #include <stb_image.h>
@@ -155,7 +160,7 @@ void UserInterface::handleMouse()
     ImGuiIO& io = ImGui::GetIO(); 
 
     // if not on any window
-    if ( !ImGui::IsAnyWindowHovered() )
+    if ( !ImGui::IsAnyWindowHovered() && !ImGui::IsAnyWindowFocused() )
     {
         // Mouse wheel over background
         if ( io.MouseWheel > 0) {
@@ -165,6 +170,22 @@ void UserInterface::handleMouse()
 
         if ( ImGui::IsMouseDown(ImGuiMouseButton_Left)) {
 
+            Log::Info("Mouse press (%.1f,%.1f)", io.MousePos.x, io.MousePos.y);
+
+            glm::mat4 mv = glm::identity<glm::mat4>();
+            glm::vec3 point = Rendering::manager().unProject(glm::vec2(io.MousePos.x, io.MousePos.y), mv);
+
+            Log::Info("            (%.1f,%.1f)", point.x, point.y);
+
+        }
+
+        if ( ImGui::IsMouseDragging(ImGuiMouseButton_Left, 10.0f) )
+        {
+            Log::Info("Mouse drag (%.1f,%.1f)(%.1f,%.1f)", io.MouseClickedPos[0].x, io.MouseClickedPos[0].y, io.MousePos.x, io.MousePos.y);
+            ImGui::GetBackgroundDrawList()->AddRect(io.MouseClickedPos[0], io.MousePos,
+                    ImGui::GetColorU32(ImGuiCol_ResizeGripHovered));
+            ImGui::GetBackgroundDrawList()->AddRectFilled(io.MouseClickedPos[0], io.MousePos,
+                    ImGui::GetColorU32(ImGuiCol_ResizeGripHovered, 0.3f));
         }
 
         if ( ImGui::IsMouseReleased(ImGuiMouseButton_Left) )
@@ -177,15 +198,15 @@ void UserInterface::handleMouse()
 
 void UserInterface::NewFrame()
 {
-    // deal with keyboard and mouse events
-    handleKeyboard();
-    handleMouse();
-
     // Start the Dear ImGui frame
     ImGui_ImplOpenGL3_NewFrame();
     ImGui_ImplGlfw_NewFrame();
     ImGui::NewFrame();
 
+    // deal with keyboard and mouse events
+    handleKeyboard();
+    handleMouse();
+
     // Main window
     mainwindow.Render();
 

main.cpp

@@ -271,7 +271,6 @@ int main(int, char**)
 
     g2.addChild(&testnode1);
     g2.addChild(&testnode2);
-    g2.setActiveIndex(1);
     scene.root_.addChild(&g2);
 
     // init output FBO