update djstdlib

src/main.cpp

@@ -25,7 +25,6 @@
 #include "lib/loaders/tinyobj.h"
 
 struct Entity;
-struct Polycube;
 struct SceneGraphNode;
 uint32 new_entity();
 Entity *get_entity(uint32 id);
@@ -104,6 +103,19 @@ struct SceneGraphNode {
     uint32 entity;
 };
 
+struct Frame {
+    uint32 width;
+    uint32 height;
+    int32 x;
+    int32 y;
+    Camera* cam;
+};
+
+struct Polycube {
+    int graph_node;
+    glm::vec3 color;
+};
+
 struct GlobalAppState {
     bool wireframe = false;
     uint32 current_polycube;
@@ -111,6 +123,7 @@ struct GlobalAppState {
     uint32 light;
     Shader *active_shader;
     std::vector<Polycube> polycubes;
+    Camera* camera;
 };
 
 GlobalAppState app_state = {};
@@ -133,11 +146,6 @@ void recalculate_sg_node(SceneGraphNode *n) {
     );
 }
 
-struct Polycube {
-    int graph_node;
-    glm::vec3 color;
-};
-
 void show_polycube(Polycube *p) {
     SceneGraphNode *node = get_scene_graph_node(p->graph_node);
     for (uint32 &child : node->children) {
@@ -167,14 +175,6 @@ glm::vec3 centreFromPolycube(Polycube *p) {
     return centre;
 }
 
-struct Frame {
-    uint32 width;
-    uint32 height;
-    int32 x;
-    int32 y;
-    Camera* cam;
-};
-
 Frame createFrame(Arena *arena, uint32 width, uint32 height, uint32 x, uint32 y) {
     Frame result = {0};
     result.width = width;
@@ -311,7 +311,11 @@ void process_input(GLFWwindow *window, Input *input, Input *prevInput) {
         }
         real64 deltaY = (input->mouse.y - prevInput->mouse.y) * 0.006;
         if (deltaY > 0.00000001 || deltaY < -0.00000001) {
-            polycube_graph_node->rotation = polycube_graph_node->rotation * glm::quat(glm::vec3(deltaY, 0, 0));
+            auto eyes = glm::normalize(app_state.camera->pos - polycube_graph_node->translation);
+            auto rotationAxis = glm::cross(eyes, glm::vec3(0, 1, 0));
+            auto localRotationAxis = glm::vec3(glm::inverse(polycube_graph_node->world) * glm::vec4(rotationAxis, 0));
+            auto rotation = glm::quat(deltaY, localRotationAxis);
+            polycube_graph_node->rotation = rotation * polycube_graph_node->rotation; 
         }
     }
 }
@@ -393,11 +397,14 @@ int main_gfx() {
         return -1;
     }
 
+    Frame main_frame = createFrame(arena, 800, 600, 0, 0);
+
     app_state.current_polycube = 0;
     app_state.last_polycube_visible = 6;
     app_state.active_shader = 0;
     app_state.polycubes = {};
     app_state.light = new_entity();
+    app_state.camera = main_frame.cam;
 
     SceneGraphNode *light_graph_node = get_scene_graph_node(get_entity(app_state.light)->scene_graph_node);
     light_graph_node->translation = glm::vec3(4.0f, 24.0f, 6.0f);
@@ -410,8 +417,6 @@ int main_gfx() {
     cube_mesh = createMesh("./assets/models/c000000.obj");
     wall_tex = createTexture("./assets/textures/brick-wall.jpg");
 
-    Frame main_frame = createFrame(arena, 800, 600, 0, 0);
-
     SceneGraphNode root_node = {};
     init_sg_node(&root_node);
 
@@ -424,8 +429,8 @@ int main_gfx() {
         root_node.children.push_back(app_state.polycubes.back().graph_node);
     }
 
-    main_frame.cam->pos = glm::vec3(4.0f, 4.0f, 4.0f);
-    camera_look_at(main_frame.cam, 0.0f, 0.0f, 0.0f);
+    app_state.camera->pos = glm::vec3(4.0f, 4.0f, 4.0f);
+    camera_look_at(app_state.camera, 0.0f, 0.0f, 0.0f);
 
     glUseProgram(app_state.active_shader->prog_id);