Metal: MTLBatch and MTLDrawList implementation.

MTLBatch and MTLDrawList implementation enables use of Metal Viewport for UI and Workbench. Includes Vertex descriptor caching and SSBO Vertex Fetch mode draw call submission.

Authored by Apple: Michael Parkin-White

Ref T96261

Reviewed By: fclem

Maniphest Tasks: T96261

Differential Revision: https://developer.blender.org/D16101

1 files changed, 77 insertions, 20 deletions

diff --git a/source/blender/gpu/metal/mtl_texture.mm b/source/blender/gpu/metal/mtl_texture.mm
index 32029db6fd9..4931f8a4f52 100644
--- a/source/blender/gpu/metal/mtl_texture.mm
+++ b/source/blender/gpu/metal/mtl_texture.mm
@@ -337,20 +337,6 @@ void gpu::MTLTexture::blit(gpu::MTLTexture *dst,
 
   GPU_batch_draw(quad);
 
-  /* TMP draw with IMM TODO(Metal): Remove this once GPUBatch is supported. */
-  GPUVertFormat *imm_format = immVertexFormat();
-  uint pos = GPU_vertformat_attr_add(imm_format, "pos", GPU_COMP_F32, 2, GPU_FETCH_FLOAT);
-
-  immBindShader(shader);
-  immBegin(GPU_PRIM_TRI_STRIP, 4);
-  immVertex2f(pos, 1, 0);
-  immVertex2f(pos, 0, 0);
-  immVertex2f(pos, 1, 1);
-  immVertex2f(pos, 0, 1);
-  immEnd();
-  immUnbindProgram();
-  /**********************/
-
   /* restoring old pipeline state. */
   GPU_depth_mask(depth_write_prev);
   GPU_stencil_write_mask_set(stencil_mask_prev);
@@ -1472,10 +1458,82 @@ bool gpu::MTLTexture::init_internal()
 
 bool gpu::MTLTexture::init_internal(GPUVertBuf *vbo)
 {
-  /* Not a valid vertex buffer format, though verifying texture is not set as such
-   * as this is not supported on Apple Silicon. */
-  BLI_assert_msg(this->format_ != GPU_DEPTH24_STENCIL8,
-                 "Apple silicon does not support GPU_DEPTH24_S8");
+  if (this->format_ == GPU_DEPTH24_STENCIL8) {
+    /* Apple Silicon requires GPU_DEPTH32F_STENCIL8 instead of GPU_DEPTH24_STENCIL8. */
+    this->format_ = GPU_DEPTH32F_STENCIL8;
+  }
+
+  MTLPixelFormat mtl_format = gpu_texture_format_to_metal(this->format_);
+  mtl_max_mips_ = 1;
+  mipmaps_ = 0;
+  this->mip_range_set(0, 0);
+
+  /* Create texture from GPUVertBuf's buffer. */
+  MTLVertBuf *mtl_vbo = static_cast<MTLVertBuf *>(unwrap(vbo));
+  mtl_vbo->bind();
+  mtl_vbo->flag_used();
+
+  /* Get Metal Buffer. */
+  id<MTLBuffer> source_buffer = mtl_vbo->get_metal_buffer();
+  BLI_assert(source_buffer);
+
+  /* Verify size. */
+  if (w_ <= 0) {
+    MTL_LOG_WARNING("Allocating texture buffer of width 0!\n");
+    w_ = 1;
+  }
+
+  /* Verify Texture and vertex buffer alignment. */
+  int bytes_per_pixel = get_mtl_format_bytesize(mtl_format);
+  int bytes_per_row = bytes_per_pixel * w_;
+
+  MTLContext *mtl_ctx = MTLContext::get();
+  uint32_t align_requirement = static_cast<uint32_t>(
+      [mtl_ctx->device minimumLinearTextureAlignmentForPixelFormat:mtl_format]);
+
+  /* Verify per-vertex size aligns with texture size. */
+  const GPUVertFormat *format = GPU_vertbuf_get_format(vbo);
+  BLI_assert(bytes_per_pixel == format->stride &&
+             "Pixel format stride MUST match the texture format stride -- These being different "
+             "is likely caused by Metal's VBO padding to a minimum of 4-bytes per-vertex");
+  UNUSED_VARS_NDEBUG(format);
+
+  /* Create texture descriptor. */
+  BLI_assert(type_ == GPU_TEXTURE_BUFFER);
+  texture_descriptor_ = [[MTLTextureDescriptor alloc] init];
+  texture_descriptor_.pixelFormat = mtl_format;
+  texture_descriptor_.textureType = MTLTextureTypeTextureBuffer;
+  texture_descriptor_.width = w_;
+  texture_descriptor_.height = 1;
+  texture_descriptor_.depth = 1;
+  texture_descriptor_.arrayLength = 1;
+  texture_descriptor_.mipmapLevelCount = mtl_max_mips_;
+  texture_descriptor_.usage =
+      MTLTextureUsageShaderRead | MTLTextureUsageShaderWrite |
+      MTLTextureUsagePixelFormatView; /* TODO(Metal): Optimise usage flags. */
+  texture_descriptor_.storageMode = [source_buffer storageMode];
+  texture_descriptor_.sampleCount = 1;
+  texture_descriptor_.cpuCacheMode = [source_buffer cpuCacheMode];
+  texture_descriptor_.hazardTrackingMode = [source_buffer hazardTrackingMode];
+
+  texture_ = [source_buffer
+      newTextureWithDescriptor:texture_descriptor_
+                        offset:0
+                   bytesPerRow:ceil_to_multiple_u(bytes_per_row, align_requirement)];
+  aligned_w_ = bytes_per_row / bytes_per_pixel;
+
+  BLI_assert(texture_);
+  texture_.label = [NSString stringWithUTF8String:this->get_name()];
+  is_baked_ = true;
+  is_dirty_ = false;
+  resource_mode_ = MTL_TEXTURE_MODE_VBO;
+
+  /* Track Status. */
+  vert_buffer_ = mtl_vbo;
+  vert_buffer_mtl_ = source_buffer;
+  /* Cleanup. */
+  [texture_descriptor_ release];
+  texture_descriptor_ = nullptr;
 
   return true;
 }
@@ -1522,7 +1580,6 @@ bool gpu::MTLTexture::texture_is_baked()
 /* Prepare texture parameters after initialization, but before baking. */
 void gpu::MTLTexture::prepare_internal()
 {
-
   /* Derive implicit usage flags for Depth/Stencil attachments. */
   if (format_flag_ & GPU_FORMAT_DEPTH || format_flag_ & GPU_FORMAT_STENCIL) {
     gpu_image_usage_flags_ |= GPU_TEXTURE_USAGE_ATTACHMENT;
@@ -1687,7 +1744,7 @@ void gpu::MTLTexture::ensure_baked()
     /* Determine Resource Mode. */
     resource_mode_ = MTL_TEXTURE_MODE_DEFAULT;
 
-    /* Create texture. */
+    /* Standard texture allocation. */
     texture_ = [ctx->device newTextureWithDescriptor:texture_descriptor_];
 
     [texture_descriptor_ release];