rolling cube

src/main.cpp

@@ -178,7 +178,7 @@ int main() {
 
     Shape plane { shader, shapes.at("square") };
     plane.init();
-    plane.translate(glm::vec3 { 0.0f, -1.0f, 0.0f });
+    plane.translate(glm::vec3 { 0.0f, -0.75f, 0.0f });
     plane.rotate(glm::radians(90.0f), glm::vec3 { 1.0f, 0.0f, 0.0f });
     plane.scale(glm::vec3 { 1.0f } * 100.0f);
 
@@ -188,6 +188,11 @@ int main() {
     long unsigned int frame { 0 };
     double last_frame_time { 0 };
 
+    struct {
+        float x;
+        float z;
+    } cube_last_pos { .x = 0.0f, .z = 0.0f };
+
     while (!glfwWindowShouldClose(window)) {
         const double current_time { glfwGetTime() };
         delta = current_time - last_frame_time;
@@ -201,6 +206,7 @@ int main() {
         process_keyboard_input(window);
 
         glClearColor(0.5f, 0.5f, 0.5f, 1.0f);
+        // glClearColor(0.0f, 0.0f, 1.0f, 1.0f);
         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
         glm::mat4 view { camera.get_view_matrix() };
@@ -222,7 +228,15 @@ int main() {
         plane.draw();
 
         shader->set_vec4("color", glm::vec4 { 1.0f, 1.0f, 1.0f, 1.0f });
-        cube.rotate(glm::radians(1.0f), glm::vec3 { 0.0f, 1.0f, 0.0f });
+        cube.reset_transform();
+        const float x { static_cast<float>(std::cos(current_time)) };
+        const float z { static_cast<float>(std::sin(current_time)) };
+        cube.translate(glm::vec3 { x, 0.0f, z } );
+        const float dx { x - cube_last_pos.x };
+        const float dz { z - cube_last_pos.z };
+        cube.rotate(glm::radians(-90.0f), glm::vec3 { dx, 0.0f, dz });
+        cube_last_pos.x = x;
+        cube_last_pos.z = z;
         cube.draw();
 
         const double time_since_last_frame { glfwGetTime() - last_frame_time };