Examples: Simplified mouse wheel handling. (#1463)

examples/marmalade_example/imgui_impl_marmalade.cpp

@@ -21,7 +21,6 @@
 // Data
 static double       g_Time = 0.0f;
 static bool         g_MousePressed[3] = { false, false, false };
-static float        g_MouseWheel = 0.0f;
 static CIwTexture*  g_FontTexture = NULL;
 static char*        g_ClipboardText = NULL;
 static bool         g_osdKeyboardEnabled = false;
@@ -128,9 +127,9 @@ int32 ImGui_Marmalade_PointerButtonEventCallback(void* SystemData, void* pUserDa
         if (pEvent->m_Button == S3E_POINTER_BUTTON_MIDDLEMOUSE)
             g_MousePressed[2] = true;
         if (pEvent->m_Button == S3E_POINTER_BUTTON_MOUSEWHEELUP)
-            g_MouseWheel += pEvent->m_y;
+            io.MouseWheel += pEvent->m_y;
         if (pEvent->m_Button == S3E_POINTER_BUTTON_MOUSEWHEELDOWN)
-            g_MouseWheel += pEvent->m_y;
+            io.MouseWheel += pEvent->m_y;
     }
 
     return 0;
@@ -282,9 +281,6 @@ void ImGui_Marmalade_NewFrame()
         g_MousePressed[i] = false;
     }
 
-    io.MouseWheel = g_MouseWheel;
-    g_MouseWheel = 0.0f;
-
     // TODO: Hide OS mouse cursor if ImGui is drawing it
     // s3ePointerSetInt(S3E_POINTER_HIDE_CURSOR,(io.MouseDrawCursor ? 0 : 1));
 

examples/opengl2_example/imgui_impl_glfw_gl2.cpp

@@ -31,7 +31,6 @@
 static GLFWwindow*  g_Window = NULL;
 static double       g_Time = 0.0f;
 static bool         g_MouseJustPressed[3] = { false, false, false };
-static ImVec2       g_MouseWheel = ImVec2(0.0f, 0.0f);
 static GLuint       g_FontTexture = 0;
 
 // This is the main rendering function that you have to implement and provide to ImGui (via setting up 'RenderDrawListsFn' in the ImGuiIO structure)
@@ -136,8 +135,9 @@ void ImGui_ImplGlfwGL2_MouseButtonCallback(GLFWwindow*, int button, int action,
 
 void ImGui_ImplGlfwGL2_ScrollCallback(GLFWwindow*, double xoffset, double yoffset)
 {
-    g_MouseWheel.x += (float)xoffset; // Use fractional mouse wheel.
-    g_MouseWheel.y += (float)yoffset;
+    ImGuiIO& io = ImGui::GetIO();
+    io.MouseWheelH += (float)xoffset;
+    io.MouseWheel += (float)yoffset;
 }
 
 void ImGui_ImplGlfwGL2_KeyCallback(GLFWwindow*, int key, int, int action, int mods)
@@ -296,10 +296,6 @@ void ImGui_ImplGlfwGL2_NewFrame()
         g_MouseJustPressed[i] = false;
     }
 
-    io.MouseWheel = g_MouseWheel.y;
-    io.MouseWheelH = g_MouseWheel.x;
-    g_MouseWheel.x = g_MouseWheel.x = 0.0f;
-
     // Hide OS mouse cursor if ImGui is drawing it
     glfwSetInputMode(g_Window, GLFW_CURSOR, io.MouseDrawCursor ? GLFW_CURSOR_HIDDEN : GLFW_CURSOR_NORMAL);
 

examples/opengl3_example/imgui_impl_glfw_gl3.cpp

@@ -25,7 +25,6 @@
 static GLFWwindow*  g_Window = NULL;
 static double       g_Time = 0.0f;
 static bool         g_MouseJustPressed[3] = { false, false, false };
-static ImVec2       g_MouseWheel = ImVec2(0.0f, 0.0f);
 static GLuint       g_FontTexture = 0;
 static int          g_ShaderHandle = 0, g_VertHandle = 0, g_FragHandle = 0;
 static int          g_AttribLocationTex = 0, g_AttribLocationProjMtx = 0;
@@ -157,8 +156,9 @@ void ImGui_ImplGlfwGL3_MouseButtonCallback(GLFWwindow*, int button, int action,
 
 void ImGui_ImplGlfwGL3_ScrollCallback(GLFWwindow*, double xoffset, double yoffset)
 {
-    g_MouseWheel.x += (float)xoffset; // Use fractional mouse wheel.
-    g_MouseWheel.y += (float)yoffset;
+    ImGuiIO& io = ImGui::GetIO();
+    io.MouseWheelH += (float)xoffset;
+    io.MouseWheel += (float)yoffset;
 }
 
 void ImGui_ImplGlfwGL3_KeyCallback(GLFWwindow*, int key, int, int action, int mods)
@@ -408,10 +408,6 @@ void ImGui_ImplGlfwGL3_NewFrame()
         g_MouseJustPressed[i] = false;
     }
 
-    io.MouseWheel = g_MouseWheel.y;
-    io.MouseWheelH = g_MouseWheel.x;
-    g_MouseWheel.x = g_MouseWheel.x = 0.0f;
-
     // Hide OS mouse cursor if ImGui is drawing it
     glfwSetInputMode(g_Window, GLFW_CURSOR, io.MouseDrawCursor ? GLFW_CURSOR_HIDDEN : GLFW_CURSOR_NORMAL);
 

examples/sdl_opengl2_example/imgui_impl_sdl_gl2.cpp

@@ -24,7 +24,6 @@
 // Data
 static double       g_Time = 0.0f;
 static bool         g_MousePressed[3] = { false, false, false };
-static ImVec2       g_MouseWheel = ImVec2(0.0f, 0.0f);
 static GLuint       g_FontTexture = 0;
 
 // This is the main rendering function that you have to implement and provide to ImGui (via setting up 'RenderDrawListsFn' in the ImGuiIO structure)
@@ -132,10 +131,10 @@ bool ImGui_ImplSdlGL2_ProcessEvent(SDL_Event* event)
     {
     case SDL_MOUSEWHEEL:
         {
-            if (event->wheel.x > 0) g_MouseWheel.x = +1;
-            if (event->wheel.x < 0) g_MouseWheel.x = -1;
-            if (event->wheel.y > 0) g_MouseWheel.y = +1;
-            if (event->wheel.y < 0) g_MouseWheel.y = -1;
+            if (event->wheel.x > 0) io.MouseWheelH += 1;
+            if (event->wheel.x < 0) io.MouseWheelH -= 1;
+            if (event->wheel.y > 0) io.MouseWheel += 1;
+            if (event->wheel.y < 0) io.MouseWheel -= 1;
             return true;
         }
     case SDL_MOUSEBUTTONDOWN:
@@ -274,13 +273,10 @@ void ImGui_ImplSdlGL2_NewFrame(SDL_Window *window)
     int mx, my;
     Uint32 mouse_buttons = SDL_GetMouseState(&mx, &my);
     io.MousePos = ImVec2(-FLT_MAX, -FLT_MAX);
-    io.MouseWheel = g_MouseWheel.y;
-    io.MouseWheelH = g_MouseWheel.x;
     io.MouseDown[0] = g_MousePressed[0] || (mouse_buttons & SDL_BUTTON(SDL_BUTTON_LEFT)) != 0;  // If a mouse press event came, always pass it as "mouse held this frame", so we don't miss click-release events that are shorter than 1 frame.
     io.MouseDown[1] = g_MousePressed[1] || (mouse_buttons & SDL_BUTTON(SDL_BUTTON_RIGHT)) != 0;
     io.MouseDown[2] = g_MousePressed[2] || (mouse_buttons & SDL_BUTTON(SDL_BUTTON_MIDDLE)) != 0;
     g_MousePressed[0] = g_MousePressed[1] = g_MousePressed[2] = false;
-    g_MouseWheel.x = g_MouseWheel.x = 0.0f;
 
     // We need to use SDL_CaptureMouse() to easily retrieve mouse coordinates outside of the client area. This is only supported from SDL 2.0.4 (released Jan 2016)
 #if (SDL_MAJOR_VERSION >= 2) && (SDL_MINOR_VERSION >= 0) && (SDL_PATCHLEVEL >= 4)   

examples/sdl_opengl3_example/imgui_impl_sdl_gl3.cpp

@@ -19,7 +19,6 @@
 // Data
 static double       g_Time = 0.0f;
 static bool         g_MousePressed[3] = { false, false, false };
-static ImVec2       g_MouseWheel = ImVec2(0.0f, 0.0f);
 static GLuint       g_FontTexture = 0;
 static int          g_ShaderHandle = 0, g_VertHandle = 0, g_FragHandle = 0;
 static int          g_AttribLocationTex = 0, g_AttribLocationProjMtx = 0;
@@ -154,10 +153,10 @@ bool ImGui_ImplSdlGL3_ProcessEvent(SDL_Event* event)
     {
     case SDL_MOUSEWHEEL:
         {
-            if (event->wheel.x > 0) g_MouseWheel.x = +1;
-            if (event->wheel.x < 0) g_MouseWheel.x = -1;
-            if (event->wheel.y > 0) g_MouseWheel.y = +1;
-            if (event->wheel.y < 0) g_MouseWheel.y = -1;
+            if (event->wheel.x > 0) io.MouseWheelH += 1;
+            if (event->wheel.x < 0) io.MouseWheelH -= 1;
+            if (event->wheel.y > 0) io.MouseWheel += 1;
+            if (event->wheel.y < 0) io.MouseWheel -= 1;
             return true;
         }
     case SDL_MOUSEBUTTONDOWN:
@@ -385,13 +384,10 @@ void ImGui_ImplSdlGL3_NewFrame(SDL_Window* window)
     int mx, my;
     Uint32 mouse_buttons = SDL_GetMouseState(&mx, &my);
     io.MousePos = ImVec2(-FLT_MAX, -FLT_MAX);
-    io.MouseWheel = g_MouseWheel.y;
-    io.MouseWheelH = g_MouseWheel.x;
     io.MouseDown[0] = g_MousePressed[0] || (mouse_buttons & SDL_BUTTON(SDL_BUTTON_LEFT)) != 0;  // If a mouse press event came, always pass it as "mouse held this frame", so we don't miss click-release events that are shorter than 1 frame.
     io.MouseDown[1] = g_MousePressed[1] || (mouse_buttons & SDL_BUTTON(SDL_BUTTON_RIGHT)) != 0;
     io.MouseDown[2] = g_MousePressed[2] || (mouse_buttons & SDL_BUTTON(SDL_BUTTON_MIDDLE)) != 0;
     g_MousePressed[0] = g_MousePressed[1] = g_MousePressed[2] = false;
-    g_MouseWheel.x = g_MouseWheel.x = 0.0f;
 
     // We need to use SDL_CaptureMouse() to easily retrieve mouse coordinates outside of the client area. This is only supported from SDL 2.0.4 (released Jan 2016)
 #if (SDL_MAJOR_VERSION >= 2) && (SDL_MINOR_VERSION >= 0) && (SDL_PATCHLEVEL >= 4)   

examples/vulkan_example/imgui_impl_glfw_vulkan.cpp

@@ -24,8 +24,7 @@
 // GLFW Data
 static GLFWwindow*  g_Window = NULL;
 static double       g_Time = 0.0f;
-static bool         g_MousePressed[3] = { false, false, false };
-static ImVec2       g_MouseWheel = ImVec2(0.0f, 0.0f);
+static bool         g_MouseJustPressed[3] = { false, false, false };
 
 // Vulkan Data
 static VkAllocationCallbacks* g_Allocator = NULL;
@@ -327,13 +326,14 @@ static void ImGui_ImplGlfwVulkan_SetClipboardText(void* user_data, const char* t
 void ImGui_ImplGlfwVulkan_MouseButtonCallback(GLFWwindow*, int button, int action, int /*mods*/)
 {
     if (action == GLFW_PRESS && button >= 0 && button < 3)
-        g_MousePressed[button] = true;
+        g_MouseJustPressed[button] = true;
 }
 
 void ImGui_ImplGlfwVulkan_ScrollCallback(GLFWwindow*, double xoffset, double yoffset)
 {
-    g_MouseWheel.x += (float)xoffset; // Use fractional mouse wheel.
-    g_MouseWheel.y += (float)yoffset;
+    ImGuiIO& io = ImGui::GetIO();
+    io.MouseWheelH += (float)xoffset;
+    io.MouseWheel += (float)yoffset;
 }
 
 void ImGui_ImplGlfwVulkan_KeyCallback(GLFWwindow*, int key, int, int action, int mods)
@@ -822,14 +822,10 @@ void ImGui_ImplGlfwVulkan_NewFrame()
 
     for (int i = 0; i < 3; i++)
     {
-        io.MouseDown[i] = g_MousePressed[i] || glfwGetMouseButton(g_Window, i) != 0;    // If a mouse press event came, always pass it as "mouse held this frame", so we don't miss click-release events that are shorter than 1 frame.
-        g_MousePressed[i] = false;
+        io.MouseDown[i] = g_MouseJustPressed[i] || glfwGetMouseButton(g_Window, i) != 0;    // If a mouse press event came, always pass it as "mouse held this frame", so we don't miss click-release events that are shorter than 1 frame.
+        g_MouseJustPressed[i] = false;
     }
 
-    io.MouseWheel = g_MouseWheel.y;
-    io.MouseWheelH = g_MouseWheel.x;
-    g_MouseWheel.x = g_MouseWheel.x = 0.0f;
-
     // Hide OS mouse cursor if ImGui is drawing it
     glfwSetInputMode(g_Window, GLFW_CURSOR, io.MouseDrawCursor ? GLFW_CURSOR_HIDDEN : GLFW_CURSOR_NORMAL);