Cleanup: Clang-Tidy, modernize-use-using

Replace `typedef` with `using` in C++ code.

In the case of `typedef struct SomeName { ... } SomeName;` I removed the
`typedef` altogether, as this is unnecessary in C++. Such cases have been
rewritten to `struct SomeName { ... };`

No functional changes.

.clang-tidy

@@ -37,7 +37,6 @@ Checks:  >
   -modernize-avoid-c-arrays,
   -modernize-use-equals-default,
   -modernize-use-nodiscard,
-  -modernize-use-using,
   -modernize-loop-convert,
   -modernize-pass-by-value,
   -modernize-use-default-member-init,

source/blender/blenlib/intern/threads.cc

@@ -132,13 +132,13 @@ static int num_threads_override = 0;
 /* just a max for security reasons */
 #define RE_MAX_THREAD BLENDER_MAX_THREADS
 
-typedef struct ThreadSlot {
+struct ThreadSlot {
   struct ThreadSlot *next, *prev;
   void *(*do_thread)(void *);
   void *callerdata;
   pthread_t pthread;
   int avail;
-} ThreadSlot;
+};
 
 void BLI_threadapi_init(void)
 {

source/blender/blenlib/tests/BLI_array_store_test.cc

@@ -32,11 +32,11 @@ static void print_mem_saved(const char *id, const BArrayStore *bs)
 /* -------------------------------------------------------------------- */
 /* Test Chunks (building data from list of chunks) */
 
-typedef struct TestChunk {
+struct TestChunk {
   struct TestChunk *next, *prev;
   const void *data;
   size_t data_len;
-} TestChunk;
+};
 
 static TestChunk *testchunk_list_add(ListBase *lb, const void *data, size_t data_len)
 {
@@ -111,14 +111,14 @@ static char *testchunk_as_data_array(TestChunk **tc_array, int tc_array_len, siz
 /* Test Buffer */
 
 /* API to handle local allocation of data so we can compare it with the data in the array_store */
-typedef struct TestBuffer {
+struct TestBuffer {
   struct TestBuffer *next, *prev;
   const void *data;
   size_t data_len;
 
   /* for reference */
   BArrayState *state;
-} TestBuffer;
+};
 
 static TestBuffer *testbuffer_list_add(ListBase *lb, const void *data, size_t data_len)
 {

source/blender/compositor/intern/COM_NodeOperationBuilder.cpp

@@ -597,7 +597,7 @@ void NodeOperationBuilder::add_complex_operation_buffers()
   }
 }
 
-typedef std::set<NodeOperation *> Tags;
+using Tags = std::set<NodeOperation *>;
 
 static void find_reachable_operations_recursive(Tags &reachable, NodeOperation *op)
 {

source/blender/compositor/operations/COM_VectorBlurOperation.cpp

@@ -294,10 +294,10 @@ static void zbuf_add_to_span(ZSpan *zspan, const float v1[2], const float v2[2])
 
 /* ******************** VECBLUR ACCUM BUF ************************* */
 
-typedef struct DrawBufPixel {
+struct DrawBufPixel {
   const float *colpoin;
   float alpha;
-} DrawBufPixel;
+};
 
 static void zbuf_fill_in_rgba(
     ZSpan *zspan, DrawBufPixel *col, float *v1, float *v2, float *v3, float *v4)

source/blender/depsgraph/intern/depsgraph_query_foreach.cc

@@ -49,7 +49,7 @@ namespace {
 
 typedef deque<OperationNode *> TraversalQueue;
 
-typedef void (*DEGForeachOperation)(OperationNode *op_node, void *user_data);
+using DEGForeachOperation = void (*)(OperationNode *, void *);
 
 bool deg_foreach_needs_visit(const OperationNode *op_node, const int flags)
 {

source/blender/freestyle/intern/view_map/ViewMapBuilder.cpp

@@ -2299,8 +2299,8 @@ struct less_SVertex2D {
   }
 };
 
-typedef Segment<FEdge *, Vec3r> segment;
-typedef Intersection<segment> intersection;
+using segment = Segment<FEdge *, Vec3r>;
+using intersection = Intersection<segment>;
 
 struct less_Intersection {
   segment *edge;

source/blender/gpu/intern/gpu_matrix.cc

@@ -39,15 +39,15 @@ using namespace blender::gpu;
 
 #define MATRIX_STACK_DEPTH 32
 
-typedef float Mat4[4][4];
-typedef float Mat3[3][3];
+using Mat4 = float[4][4];
+using Mat3 = float[3][3];
 
-typedef struct MatrixStack {
+struct MatrixStack {
   Mat4 stack[MATRIX_STACK_DEPTH];
   uint top;
-} MatrixStack;
+};
 
-typedef struct GPUMatrixState {
+struct GPUMatrixState {
   MatrixStack model_view_stack;
   MatrixStack projection_stack;
 
@@ -59,7 +59,7 @@ typedef struct GPUMatrixState {
    * TODO: separate Model from View transform? Batches/objects have model,
    * camera/eye has view & projection
    */
-} GPUMatrixState;
+};
 
 #define ModelViewStack Context::get()->matrix_state->model_view_stack
 #define ModelView ModelViewStack.stack[ModelViewStack.top]

source/blender/gpu/intern/gpu_select_sample_query.cc

@@ -47,7 +47,7 @@
 using namespace blender;
 using namespace blender::gpu;
 
-typedef struct GPUSelectQueryState {
+struct GPUSelectQueryState {
   /* Tracks whether a query has been issued so that gpu_load_id can end the previous one */
   bool query_issued;
   /* GPU queries abstraction. Contains an array of queries. */
@@ -68,7 +68,7 @@ typedef struct GPUSelectQueryState {
   int scissor[4];
   eGPUWriteMask write_mask;
   eGPUDepthTest depth_test;
-} GPUSelectQueryState;
+};
 
 static GPUSelectQueryState g_query_state = {false};
 

source/blender/gpu/opengl/gl_drawlist.cc

@@ -43,20 +43,20 @@
 
 using namespace blender::gpu;
 
-typedef struct GLDrawCommand {
+struct GLDrawCommand {
   GLuint v_count;
   GLuint i_count;
   GLuint v_first;
   GLuint i_first;
-} GLDrawCommand;
+};
 
-typedef struct GLDrawCommandIndexed {
+struct GLDrawCommandIndexed {
   GLuint v_count;
   GLuint i_count;
   GLuint v_first;
   GLuint base_index;
   GLuint i_first;
-} GLDrawCommandIndexed;
+};
 
 #define MDI_ENABLED (buffer_size_ != 0)
 #define MDI_DISABLED (buffer_size_ == 0)

source/blender/ikplugin/intern/itasc_plugin.cpp

@@ -73,8 +73,8 @@ struct IK_Data {
   struct IK_Scene *first;
 };
 
-typedef float Vector3[3];
-typedef float Vector4[4];
+using Vector3 = float[3];
+using Vector4 = float[4];
 struct IK_Target;
 typedef void (*ErrorCallback)(const iTaSC::ConstraintValues *values,
                               unsigned int nvalues,

source/blender/imbuf/intern/openexr/openexr_api.cpp

@@ -620,7 +620,7 @@ bool imb_save_openexr(struct ImBuf *ibuf, const char *name, int flags)
 
 static ListBase exrhandles = {nullptr, nullptr};
 
-typedef struct ExrHandle {
+struct ExrHandle {
   struct ExrHandle *next, *prev;
   char name[FILE_MAX];
 
@@ -645,10 +645,10 @@ typedef struct ExrHandle {
   ListBase layers;   /* hierarchical, pointing in end to ExrChannel */
 
   int num_half_channels; /* used during filr save, allows faster temporary buffers allocation */
-} ExrHandle;
+};
 
 /* flattened out channel */
-typedef struct ExrChannel {
+struct ExrChannel {
   struct ExrChannel *next, *prev;
 
   char name[EXR_TOT_MAXNAME + 1]; /* full name with everything */
@@ -658,10 +658,10 @@ typedef struct ExrChannel {
   char chan_id;                   /* quick lookup of channel char */
   int view_id;                    /* quick lookup of channel view */
   bool use_half_float;            /* when saving use half float for file storage */
-} ExrChannel;
+};
 
 /* hierarchical; layers -> passes -> channels[] */
-typedef struct ExrPass {
+struct ExrPass {
   struct ExrPass *next, *prev;
   char name[EXR_PASS_MAXNAME];
   int totchan;
@@ -672,13 +672,13 @@ typedef struct ExrPass {
   char internal_name[EXR_PASS_MAXNAME]; /* name with no view */
   char view[EXR_VIEW_MAXNAME];
   int view_id;
-} ExrPass;
+};
 
-typedef struct ExrLayer {
+struct ExrLayer {
   struct ExrLayer *next, *prev;
   char name[EXR_LAY_MAXNAME + 1];
   ListBase passes;
-} ExrLayer;
+};
 
 /* ********************** */
 

source/blender/simulation/intern/hair_volume.cpp

@@ -76,12 +76,12 @@ typedef struct HairGridVert {
   float velocity_smooth[3];
 } HairGridVert;
 
-typedef struct HairGrid {
+struct HairGrid {
   HairGridVert *verts;
   int res[3];
   float gmin[3], gmax[3];
   float cellsize, inv_cellsize;
-} HairGrid;
+};
 
 #define HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, axis) \
   (min_ii(max_ii((int)((vec[axis] - gmin[axis]) * scale), 0), res[axis] - 2))