From 6e8a394d5f4bb0f8a364388b5c2960b8cbd8dea7 Mon Sep 17 00:00:00 2001
From: tanmaysachan <tnmysachan@gmail.com>
Date: Mon, 12 Aug 2024 00:31:13 +0530
Subject: [PATCH] Add vertex and index buffer persistence

---
 src/metal/rt64_metal.h  | 11 ++++++++++-
 src/metal/rt64_metal.mm | 30 ++++++++++++++++++++++++++----
 2 files changed, 36 insertions(+), 5 deletions(-)

diff --git a/src/metal/rt64_metal.h b/src/metal/rt64_metal.h
index c65f1db..e0f9a72 100755
--- a/src/metal/rt64_metal.h
+++ b/src/metal/rt64_metal.h
@@ -42,7 +42,7 @@ namespace RT64 {
         MTLDepthClipMode depthClipMode = MTLDepthClipModeClip;
         MTLWinding winding = MTLWindingClockwise;
 #endif
-    }
+    };
 
     struct MetalDescriptorSet : RenderDescriptorSet {
         MetalDevice *device = nullptr;
@@ -107,6 +107,11 @@ namespace RT64 {
         MTLIndexType currentIndexType = MTLIndexTypeUInt32;
         id<MTLBuffer> indexBuffer = nil;
 
+        uint32_t viewCount = 0;
+        std::vector<id<MTLBuffer>> vertexBuffers;
+        std::vector<uint32_t> vertexBufferOffsets;
+        std::vector<uint32_t> vertexBufferIndices;
+
         std::vector<MTLViewport> viewportVector;
         std::vector<MTLScissorRect> scissorVector;
 #endif
@@ -309,6 +314,10 @@ namespace RT64 {
     };
 
     struct MetalGraphicsPipeline : MetalPipeline {
+#ifdef __OBJC__
+        id<MTLRenderPipelineState> state = nil;
+#endif
+
         MetalRenderState *renderState;
         MetalGraphicsPipeline(MetalDevice *device, const RenderGraphicsPipelineDesc &desc);
         ~MetalGraphicsPipeline() override;
diff --git a/src/metal/rt64_metal.mm b/src/metal/rt64_metal.mm
index 0301ffd..3f2fae9 100755
--- a/src/metal/rt64_metal.mm
+++ b/src/metal/rt64_metal.mm
@@ -681,6 +681,7 @@ namespace RT64 {
 
         NSError *error = nullptr;
         this->state = [device->device newRenderPipelineStateWithDescriptor: descriptor error: &error];
+        renderState->renderPipelineState = state;
 
         if (error != nullptr) {
             fprintf(stderr, "MTLDevice newRenderPipelineStateWithDescriptor: failed with error %s.\n", [error.localizedDescription cStringUsingEncoding: NSUTF8StringEncoding]);
@@ -872,6 +873,12 @@ namespace RT64 {
 
             [renderEncoder setViewports: viewportVector.data() count: viewportVector.size()];
             [renderEncoder setScissorRects: scissorVector.data() count: scissorVector.size()];
+
+            for (uint32_t i = 0; i < viewCount; i++) {
+                [renderEncoder setVertexBuffer: vertexBuffers[i]
+                                        offset: vertexBufferOffsets[i]
+                                       atIndex: vertexBufferIndices[i]];
+            }
         }
     }
 
@@ -958,7 +965,7 @@ namespace RT64 {
                 guaranteeRenderEncoder();
                 const auto *graphicsPipeline = static_cast<const MetalGraphicsPipeline *>(interfacePipeline);
                 assert(renderEncoder != nil && "Cannot set pipeline state on nil MTLRenderCommandEncoder!");
-                rebindRenderState(graphicsPipeline->state);
+                rebindRenderState(graphicsPipeline->renderState);
                 break;
             }
             default:
@@ -1012,17 +1019,32 @@ namespace RT64 {
     }
 
     void MetalCommandList::setIndexBuffer(const RenderIndexBufferView *view) {
-        // TODO: Argument Buffer Creation & Binding
         if (view != nullptr) {
             const auto *interfaceBuffer = static_cast<const MetalBuffer *>(view->buffer.ref);
-
+            indexBuffer = interfaceBuffer->buffer;
         }
     }
 
     void MetalCommandList::setVertexBuffers(uint32_t startSlot, const RenderVertexBufferView *views, uint32_t viewCount, const RenderInputSlot *inputSlots) {
-        // TODO: Argument Buffer Creation & Binding
         if ((views != nullptr) && (viewCount > 0)) {
+            guaranteeRenderEncoder();
             assert(inputSlots != nullptr);
+
+            this->viewCount = viewCount;
+            vertexBuffers.clear();
+            vertexBufferOffsets.clear();
+            vertexBufferIndices.clear();
+
+            for (uint32_t i = 0; i < viewCount; i++) {
+                const MetalBuffer *interfaceBuffer = static_cast<const MetalBuffer *>(views[i].buffer.ref);
+                vertexBuffers.emplace_back(interfaceBuffer->buffer);
+                vertexBufferOffsets.emplace_back(views[i].buffer.offset);
+                vertexBufferIndices.emplace_back(startSlot + i);
+
+                [renderEncoder setVertexBuffer: interfaceBuffer->buffer
+                                        offset: views[i].buffer.offset
+                                       atIndex: startSlot + i];
+            }
         }
     }