Mouse hover

Not perfectly accurate yet, need to find out why

chunkindex.cpp

@@ -406,3 +406,25 @@ void ChunkGrid::FromIX(int ix, int& x, int& y, int& z) {
   y = ix / zdim;
   z = ix % zdim;
 }
+
+bool AABB::IntersectRay(const glm::vec3& o, const glm::vec3& d) {
+  glm::vec3 inv_dir = 1.0f / d;
+  glm::vec3 t0 = (lb - o) * inv_dir;
+  glm::vec3 t1 = (ub - o) * inv_dir;
+
+  if (inv_dir.x < 0) {
+    std::swap(t0.x, t1.x);
+  }
+  if (inv_dir.y < 0) {
+    std::swap(t0.y, t1.y);
+  }
+  if (inv_dir.z < 0) {
+    std::swap(t0.z, t1.z);
+  }
+
+  float t00 = std::max(t0.z, std::max(t0.y, t0.x));
+  float t11 = std::min(t1.z, std::min(t1.y, t1.x));
+
+  if (0 <= t11 && t00 <= t11) return true;
+  else return false;
+}

chunkindex.hpp

@@ -62,6 +62,7 @@ class AABB {
     else if (ret.z > ub.z) ret.z = ub.z;
     return ret;
   }
+  bool IntersectRay(const glm::vec3& o, const glm::vec3& d);
 };
 
 // Indices for multiple Chunk's

main.cpp

@@ -58,6 +58,19 @@ char g_cam_dx = 0,   g_cam_dy = 0,   g_cam_dz = 0,  // CONTROL axes, not OpenGL
      g_arrow_dx = 0, g_arrow_dy = 0, g_arrow_dz = 0;
 std::bitset<18> g_cam_flags;
 
+glm::vec3 WindowCoordToPickRayDir(Camera* cam, int x, int y) {
+  glm::vec3 cam_right = glm::normalize(glm::cross(cam->lookdir, cam->up));
+  glm::vec3 cam_up = glm::normalize(cam->up);
+  float u = (x * 2.0f / WIN_W) - 1.0f;
+  float v = -((y * 2.0f / WIN_H) - 1.0f);
+  const float t = tanf(30.0f / (180.0f / 3.14159f));
+  v = v * t;
+  u = u * t * WIN_W / WIN_H;
+  glm::vec3 ret = cam_right * u + cam_up * v + cam->lookdir;
+  ret = glm::normalize(ret);
+  return ret;
+}
+
 // These are all scaffolds
 Triangle *g_triangle[2];
 ColorCube *g_colorcube[2];
@@ -105,6 +118,8 @@ bool g_aa = true, g_shadows = true;
 unsigned g_test_tri_vao;
 unsigned g_test_quad_vao;
 
+int g_mouse_x = 0, g_mouse_y = 0;
+
 void MyInit() {
   {
     float vertices[] = {

main_d3d.cpp

@@ -3,6 +3,7 @@
 #pragma comment(lib, "dxguid.lib")
 
 #include <Windows.h>
+#include <windowsx.h>  // GET_{X,Y}_LPARAM
 #undef max
 #undef min
 
@@ -50,6 +51,9 @@ extern MainMenu* g_mainmenu;
 extern Chunk* ALLNULLS[26];
 extern TextMessage* g_textmessage;
 extern Particles*  g_particles;
+extern int g_mouse_x, g_mouse_y;
+extern glm::vec3 WindowCoordToPickRayDir(Camera* cam, int x, int y);
+int g_titlebar_size;
 
 bool init_done = false;
 ID3D11Device *g_device11;
@@ -598,6 +602,12 @@ void CreateCyclimbWindow() {
     WIN_W, WIN_H,
     nullptr, nullptr,
     hinstance, nullptr);
+
+  TITLEBARINFOEX* ptinfo = (TITLEBARINFOEX*)malloc(sizeof(TITLEBARINFOEX));
+  ptinfo->cbSize = sizeof(TITLEBARINFOEX);
+  SendMessage(g_hwnd, WM_GETTITLEBARINFOEX, 0, (LPARAM)ptinfo);
+  g_titlebar_size = ptinfo->rcTitleBar.bottom - ptinfo->rcTitleBar.top;
+  delete ptinfo;
 }
 
 int main_d3d11(int argc, char** argv) {
@@ -1022,6 +1032,11 @@ void OnKeyUp(WPARAM wParam, LPARAM lParam) {
   else GetCurrentGameScene()->OnKeyReleased(char(tolower(wParam)));
 }
 
+void OnMouseMove(int x, int y) {
+  g_mouse_x = x;
+  g_mouse_y = y + g_titlebar_size;
+}
+
 LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam)
 {
   switch (message)
@@ -1048,6 +1063,9 @@ LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam)
     }
     update();
     break;
+  case WM_MOUSEMOVE:
+    OnMouseMove(GET_X_LPARAM(lparam), GET_Y_LPARAM(lparam));
+    break;
   default:
     return DefWindowProc(hwnd, message, wparam, lparam);
   }

scene.cpp

@@ -82,6 +82,8 @@ const float ClimbScene::INVERSE_INERTIA = 0.05f;
 extern bool IsGL();
 extern bool IsD3D11();
 extern bool IsD3D12();
+extern glm::vec3 WindowCoordToPickRayDir(Camera* cam, int x, int y);
+extern int g_mouse_x, g_mouse_y;
 
 const glm::vec3 ClimbScene::PLAYER_ROPE_ENDPOINT[8] = 
   {
@@ -161,8 +163,15 @@ void ClimbScene::PrepareSpriteListForRender() {
       ChunkSprite* csp = dynamic_cast<ChunkSprite*>(sp);
       if (csp) {
         AABB aabb = csp->GetAABBInWorld();
-        if (campos.x >= aabb.lb.x && campos.x <= aabb.ub.x &&
-          campos.y >= aabb.lb.y && campos.y <= aabb.ub.y) {
+
+        glm::vec3 pickray_dir = WindowCoordToPickRayDir(camera, g_mouse_x, g_mouse_y);
+        glm::vec3 pickray_orig = camera->pos;
+
+        bool x1 = (campos.x >= aabb.lb.x && campos.x <= aabb.ub.x &&
+          campos.y >= aabb.lb.y && campos.y <= aabb.ub.y);
+        bool x2 = aabb.IntersectRay(pickray_orig, pickray_dir);
+
+        if (x1 || x2) {
           highlight_sprite->pos = sp->pos;
           float phase = fabs(sin(light_phase * 4));
           highlight_sprite->scale.x = (aabb.ub.x - aabb.lb.x) + phase + 1;