1 files changed, 135 insertions, 0 deletions
diff --git a/source/blender/gpu/metal/mtl_batch.hh b/source/blender/gpu/metal/mtl_batch.hh
new file mode 100644
index 00000000000..9e179e662b5
--- /dev/null
+++ b/source/blender/gpu/metal/mtl_batch.hh
@@ -0,0 +1,135 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+/** \file
+ * \ingroup gpu
+ *
+ * GPU geometry batch
+ * Contains VAOs + VBOs + Shader representing a drawable entity.
+ */
+
+#pragma once
+
+#include "MEM_guardedalloc.h"
+#include "gpu_batch_private.hh"
+#include "mtl_index_buffer.hh"
+#include "mtl_primitive.hh"
+#include "mtl_shader.hh"
+#include "mtl_vertex_buffer.hh"
+
+namespace blender::gpu {
+
+class MTLContext;
+class MTLShaderInterface;
+
+#define GPU_VAO_STATIC_LEN 64
+
+struct VertexBufferID {
+  uint32_t id : 16;
+  uint32_t is_instance : 15;
+  uint32_t used : 1;
+};
+
+class MTLBatch : public Batch {
+
+  /* Vertex Bind-state Caching for a given shader interface used with the Batch. */
+  struct VertexDescriptorShaderInterfacePair {
+    MTLVertexDescriptor vertex_descriptor{};
+    const ShaderInterface *interface = nullptr;
+    uint16_t attr_mask{};
+    int num_buffers{};
+    VertexBufferID bufferIds[GPU_BATCH_VBO_MAX_LEN] = {};
+    /* Cache life index compares a cache entry with the active MTLBatch state.
+     * This is initially set to the cache life index of MTLBatch. If the batch has been modified,
+     * this index is incremented to cheaply invalidate existing cache entries.  */
+    uint32_t cache_life_index = 0;
+  };
+
+  class MTLVertexDescriptorCache {
+
+   private:
+    MTLBatch *batch_;
+
+    VertexDescriptorShaderInterfacePair cache_[GPU_VAO_STATIC_LEN] = {};
+    MTLContext *cache_context_ = nullptr;
+    uint32_t cache_life_index_ = 0;
+
+   public:
+    MTLVertexDescriptorCache(MTLBatch *batch) : batch_(batch){};
+    VertexDescriptorShaderInterfacePair *find(const ShaderInterface *interface);
+    bool insert(VertexDescriptorShaderInterfacePair &data);
+
+   private:
+    void vertex_descriptor_cache_init(MTLContext *ctx);
+    void vertex_descriptor_cache_clear();
+    void vertex_descriptor_cache_ensure();
+  };
+
+ private:
+  MTLShader *active_shader_ = nullptr;
+  bool shader_in_use_ = false;
+  MTLVertexDescriptorCache vao_cache = {this};
+
+  /* Topology emulation. */
+  gpu::MTLBuffer *emulated_topology_buffer_ = nullptr;
+  GPUPrimType emulated_topology_type_;
+  uint32_t topology_buffer_input_v_count_ = 0;
+  uint32_t topology_buffer_output_v_count_ = 0;
+
+ public:
+  MTLBatch(){};
+  ~MTLBatch(){};
+
+  void draw(int v_first, int v_count, int i_first, int i_count) override;
+  void draw_indirect(GPUStorageBuf *indirect_buf, intptr_t offset) override
+  {
+    /* TODO(Metal): Support indirect draw commands. */
+  }
+  void multi_draw_indirect(GPUStorageBuf *indirect_buf,
+                           int count,
+                           intptr_t offset,
+                           intptr_t stride) override
+  {
+    /* TODO(Metal): Support indirect draw commands. */
+  }
+
+  /* Returns an initialized RenderComandEncoder for drawing if all is good.
+   * Otherwise, nil. */
+  id<MTLRenderCommandEncoder> bind(uint v_first, uint v_count, uint i_first, uint i_count);
+  void unbind();
+
+  /* Convenience getters. */
+  MTLIndexBuf *elem_() const
+  {
+    return static_cast<MTLIndexBuf *>(unwrap(elem));
+  }
+  MTLVertBuf *verts_(const int index) const
+  {
+    return static_cast<MTLVertBuf *>(unwrap(verts[index]));
+  }
+  MTLVertBuf *inst_(const int index) const
+  {
+    return static_cast<MTLVertBuf *>(unwrap(inst[index]));
+  }
+  MTLShader *active_shader_get() const
+  {
+    return active_shader_;
+  }
+
+ private:
+  void shader_bind();
+  void draw_advanced(int v_first, int v_count, int i_first, int i_count);
+  int prepare_vertex_binding(MTLVertBuf *verts,
+                             MTLRenderPipelineStateDescriptor &desc,
+                             const MTLShaderInterface *interface,
+                             uint16_t &attr_mask,
+                             bool instanced);
+
+  id<MTLBuffer> get_emulated_toplogy_buffer(GPUPrimType &in_out_prim_type, uint32_t &v_count);
+
+  void prepare_vertex_descriptor_and_bindings(
+      MTLVertBuf **buffers, int &num_buffers, int v_first, int v_count, int i_first, int i_count);
+
+  MEM_CXX_CLASS_ALLOC_FUNCS("MTLBatch");
+};
+
+}  // namespace blender::gpu