camera shake

src/entity.h

@@ -34,6 +34,8 @@ enum entity_prop {
     ENTITY_PROP_BULLET,
     ENTITY_PROP_TRACER,
 
+    ENTITY_PROP_QUAKE,
+
     ENTITY_PROP_ATTACHED,
 
     /* Test props */
@@ -246,6 +248,14 @@ struct entity {
     struct v2 tracer_gradient_start;
     struct v2 tracer_gradient_end;
 
+    /* ====================================================================== */
+    /* Quake */
+
+    /* ENTITY_PROP_QUAKE */
+
+    f32 quake_intensity;
+    f32 quake_fade;         /* How much intensity to lose per second */
+
     /* ====================================================================== */
     /* Testing */
 
@@ -269,6 +279,8 @@ struct entity {
     u32 camera_lerp_continuity_gen;
     struct xform camera_xform_target;  /* Calculated from camera_follow */
     u32 camera_applied_lerp_continuity_gen_plus_one;  /* Calculated */
+
+    f32 shake;
 };
 
 struct entity_array {

src/game.c

@@ -222,7 +222,7 @@ INTERNAL void spawn_test_entities(void)
     }
 
     /* Enemy */
-#if 0
+#if 1
     {
         struct entity *e = entity_alloc(root);
 
@@ -1144,23 +1144,33 @@ INTERNAL void game_update(struct game_cmd_array game_cmds)
                 tracer->tracer_gradient_end = pos;
                 tracer->tracer_gradient_start = v2_sub(pos, v2_mul(ent->linear_velocity, tracer->tracer_fade_duration));
             }
+
+            /* Spawn quake */
+            {
+                struct entity *quake = entity_alloc(root);
+                entity_set_xform(quake, XFORM_POS(pos));
+                quake->quake_intensity = 0.02f;
+                quake->quake_fade = quake->quake_intensity / 0.01f;
+                entity_enable_prop(quake, ENTITY_PROP_QUAKE);
+            }
         }
     }
 
     /* ========================== *
-     * Update camera position
+     * Update cameras
      * ========================== */
 
     for (u64 entity_index = 0; entity_index < store->reserved; ++entity_index) {
         struct entity *ent = &store->entities[entity_index];
         if (!entity_is_valid_and_active(ent)) continue;
+        if (!entity_has_prop(ent, ENTITY_PROP_CAMERA)) continue;
+
+        struct xform xf = entity_get_xform(ent);
 
         /* Camera follow */
-        if (entity_has_prop(ent, ENTITY_PROP_CAMERA)) {
+        {
             struct entity *follow = entity_from_handle(store, ent->camera_follow);
 
-            struct xform xf = entity_get_xform(ent);
-
             f32 aspect_ratio = 1.0;
             {
                 struct xform quad_xf = xform_mul(entity_get_xform(ent), ent->camera_quad_xform);
@@ -1185,7 +1195,35 @@ INTERNAL void game_update(struct game_cmd_array game_cmds)
                 xf = ent->camera_xform_target;
             }
             ent->camera_applied_lerp_continuity_gen_plus_one = ent->camera_lerp_continuity_gen + 1;
-            entity_set_xform(ent, xf);
+        }
+
+        /* Camera shake */
+        {
+            /* TODO: Update based on distance to quake */
+            ent->shake = 0;
+            for (u64 quake_ent_index = 0; quake_ent_index < store->reserved; ++quake_ent_index) {
+                struct entity *quake = &store->entities[quake_ent_index];
+                if (!entity_is_valid_and_active(quake)) continue;
+                if (!entity_has_prop(quake, ENTITY_PROP_QUAKE)) continue;
+                ent->shake += quake->quake_intensity;
+            }
+        }
+
+        entity_set_xform(ent, xf);
+    }
+
+    /* ========================== *
+     * Update quakes
+     * ========================== */
+
+    for (u64 entity_index = 0; entity_index < store->reserved; ++entity_index) {
+        struct entity *ent = &store->entities[entity_index];
+        if (!entity_is_valid_and_active(ent)) continue;
+        if (!entity_has_prop(ent, ENTITY_PROP_QUAKE)) continue;
+
+        ent->quake_intensity = max_f32(0, ent->quake_intensity - (ent->quake_fade * dt));
+        if (ent->quake_intensity <= 0) {
+            entity_enable_prop(ent, ENTITY_PROP_RELEASE_NEXT_TICK);
         }
     }
 

src/user.c

@@ -388,10 +388,6 @@ INTERNAL void pubilsh_game_cmds(struct game_cmd_list *list)
     scratch_end(scratch);
 }
 
-/* ========================== *
- * Update
- * ========================== */
-
 /* TODO: remove this (testing) */
 INTERNAL void debug_draw_xform(struct xform xf, u32 color_x, u32 color_y)
 {
@@ -432,24 +428,9 @@ INTERNAL void debug_draw_movement(struct entity *ent)
     draw_solid_arrow_ray(G.viewport_canvas, pos, vel_ray, thickness, arrow_len, color_vel);
 }
 
-
+/* ========================== *
-
+ * Update
-
+ * ========================== */
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
 
 INTERNAL void user_update(void)
 {
@@ -541,6 +522,7 @@ INTERNAL void user_update(void)
 
                     e->camera_quad_xform = xform_lerp(e0->camera_quad_xform, e1->camera_quad_xform, tick_blend);
                     e->camera_xform_target = xform_lerp(e0->camera_xform_target, e1->camera_xform_target, tick_blend);
+                    e->shake = math_lerp(e0->shake, e1->shake, tick_blend);
 
                     e->tracer_gradient_start = v2_lerp(e0->tracer_gradient_start, e1->tracer_gradient_start, tick_blend);
                     e->tracer_gradient_end = v2_lerp(e0->tracer_gradient_end, e1->tracer_gradient_end, tick_blend);
@@ -693,9 +675,24 @@ INTERNAL void user_update(void)
         G.debug_camera = !G.debug_camera;
     }
 
+    /* ========================== *
+     * Apply shake
+     * ========================== */
+
+    for (u64 entity_index = 0; entity_index < store->reserved; ++entity_index) {
+        struct entity *ent = &store->entities[entity_index];
+        if (!entity_is_valid_and_active(ent)) continue;
+        if (ent->shake <= 0) continue;
+
+        f32 shake = ent->shake;
+
+        struct xform xf = entity_get_xform(ent);
+        xf.og = v2_add(xf.og, v2_mul(v2_from_angle(sys_rand_f32(0, TAU)), shake));
+        entity_set_xform(ent, xf);
+    }
 
     /* ========================== *
-     * Update viewport
+     * Update viewport from camera
      * ========================== */
 
     /* Calculate screen viewport dimensions */
@@ -734,7 +731,7 @@ INTERNAL void user_update(void)
     G.viewport_cursor = v2_sub(G.screen_cursor, G.viewport_screen_offset);
 
     /* ========================== *
-     * Update view
+     * Update view from camera
      * ========================== */
 
     if (G.debug_camera) {
@@ -798,7 +795,7 @@ INTERNAL void user_update(void)
     G.world_cursor = xform_invert_mul_v2(G.world_view, G.viewport_cursor);
 
     /* ========================== *
-     * Update listener
+     * Update listener from view
      * ========================== */
 
     {