From 69cca0d308216861d678d30ae9a3c51ab14aca6a Mon Sep 17 00:00:00 2001
From: Abdelrahman <said.abdelrahman89@gmail.com>
Date: Tue, 24 Sep 2024 00:40:34 +0100
Subject: [PATCH] Attempt to fix first person camera implementation

---
 src/main.cc | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/src/main.cc b/src/main.cc
index 484ab16..dca429b 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -25,8 +25,10 @@
 #include <string>
 #include <vector>
 
-#define WINDOW_WIDTH 1280
-#define WINDOW_HEIGHT 720
+#define WINDOW_WIDTH       1280
+#define WINDOW_HEIGHT      720
+#define WINDOW_HALF_WIDTH  640
+#define WINDOW_HALF_HEIGHT 360
 
 enum exit_codes : int {
   EXIT_CODE_SUCCESS,
@@ -84,6 +86,9 @@ struct App {
   glm::mat4     projection_mat;
   GLint         u_projection_idx;
 
+  glm::vec2     current_mouse;
+  glm::vec2     prev_mouse;
+
   bool          running;
 };
 
@@ -132,6 +137,7 @@ int init(App &app) {
     return EXIT_CODE_WINDOW_CREATION_FAILED;
   }
 
+  SDL_WarpMouseInWindow(app.window, WINDOW_HALF_WIDTH, WINDOW_HALF_HEIGHT);
   SDL_SetRelativeMouseMode(SDL_TRUE);
 
   SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 4);
@@ -173,6 +179,8 @@ int init(App &app) {
                                                0.1f,
                                                20.0f
                               );
+  app.current_mouse         = glm::vec2(WINDOW_HALF_WIDTH, WINDOW_HALF_HEIGHT);
+  app.prev_mouse            = glm::vec2(WINDOW_HALF_WIDTH, WINDOW_HALF_HEIGHT);
 
   return EXIT_CODE_SUCCESS;
 }
@@ -431,9 +439,12 @@ void handle_object_movement(App &app) {
 
 void handle_camera_movement(App &app) {
   if (app.event.type == SDL_MOUSEMOTION) {
+    app.current_mouse        += glm::vec2(app.event.motion.xrel, app.event.motion.yrel);
+    glm::vec2 mouse_delta     = app.prev_mouse - app.current_mouse;
     app.camera.view_direction = glm::rotate(app.camera.view_direction,
-                                            glm::radians((float)app.event.motion.xrel * -0.5f),
+                                            glm::radians(mouse_delta.x),
                                             app.camera.up_vector);
+    app.prev_mouse            = app.current_mouse;
   } else {
     switch (app.event.key.keysym.sym) {
       case SDLK_w: