lib: Refer to active camera in r->scene instead of copying

For interactive rendering mode, any changes to the scene state will need
to be reflected seen by worker threads too, and we have no reason to do
a copy here anyway.

src/lib/renderer/renderer.c

@@ -115,11 +115,11 @@ void renderer_render(struct renderer *r) {
 		logr(warning, "Unable to catch SIGINT\n");
 	}
 
-	struct camera camera = r->scene->cameras.items[r->prefs.selected_camera];
+	struct camera *camera = &r->scene->cameras.items[r->prefs.selected_camera];
 	if (r->prefs.override_width && r->prefs.override_height) {
-		camera.width = r->prefs.override_width ? (int)r->prefs.override_width : camera.width;
-		camera.height = r->prefs.override_height ? (int)r->prefs.override_height : camera.height;
-		cam_recompute_optics(&camera);
+		camera->width = r->prefs.override_width ? (int)r->prefs.override_width : camera->width;
+		camera->height = r->prefs.override_height ? (int)r->prefs.override_height : camera->height;
+		cam_recompute_optics(camera);
 	}
 
 	// Verify we have at least a single thread rendering.
@@ -132,7 +132,7 @@ void renderer_render(struct renderer *r) {
 		r->scene->background = newBackground(&r->scene->storage, NULL, NULL, NULL, r->scene->use_blender_coordinates);
 	}
 
-	struct tile_set set = tile_quantize(camera.width, camera.height, r->prefs.tileWidth, r->prefs.tileHeight, r->prefs.tileOrder);
+	struct tile_set set = tile_quantize(camera->width, camera->height, r->prefs.tileWidth, r->prefs.tileHeight, r->prefs.tileOrder);
 
 	for (size_t i = 0; i < r->scene->shader_buffers.count; ++i) {
 		if (!r->scene->shader_buffers.items[i].bsdfs.count) {
@@ -182,11 +182,11 @@ void renderer_render(struct renderer *r) {
 	// Render buffer is used to store accurate color values for the renderers' internal use
 	if (!r->state.result_buf) {
 		// Allocate
-		r->state.result_buf = newTexture(float_p, camera.width, camera.height, 4);
-	} else if (r->state.result_buf->width != (size_t)camera.width || r->state.result_buf->height != (size_t)camera.height) {
+		r->state.result_buf = newTexture(float_p, camera->width, camera->height, 4);
+	} else if (r->state.result_buf->width != (size_t)camera->width || r->state.result_buf->height != (size_t)camera->height) {
 		// Resize
 		if (r->state.result_buf) destroyTexture(r->state.result_buf);
-		r->state.result_buf = newTexture(float_p, camera.width, camera.height, 4);
+		r->state.result_buf = newTexture(float_p, camera->width, camera->height, 4);
 	} else {
 		// Clear
 		tex_clear(r->state.result_buf);
@@ -225,7 +225,7 @@ void renderer_render(struct renderer *r) {
 		worker_arr_add(&r->state.workers, (struct worker){
 			.renderer = r,
 			.buf = result,
-			.cam = &camera,
+			.cam = camera,
 			.thread = (struct cr_thread){
 				.thread_fn = local_render_thread,
 			}
@@ -236,7 +236,7 @@ void renderer_render(struct renderer *r) {
 			.client = &r->state.clients.items[c],
 			.renderer = r,
 			.buf = result,
-			.cam = &camera,
+			.cam = camera,
 			.thread = (struct cr_thread){
 				.thread_fn = client_connection_thread
 			}