From e42986adc345d9d630da42b8343b1223e05a7105 Mon Sep 17 00:00:00 2001
From: Camden Dixie O'Brien <cobrien@witekio.com>
Date: Wed, 1 Oct 2025 16:10:54 +0100
Subject: [PATCH] Create buffer for bone matrices

---
 gpu.c | 16 ++++++++++++++++
 gpu.h |  3 +++
 2 files changed, 19 insertions(+)

diff --git a/gpu.c b/gpu.c
index 646fc9a..7a5a8c7 100644
--- a/gpu.c
+++ b/gpu.c
@@ -462,6 +462,18 @@ void gpu_init(gpu_ctx_t *ctx, const gpu_config_t *config, model_t model)
 	    ctx->dev, ctx->mvp_buffer_mem, 0, mvp_buffer_size, 0,
 	    (void **)&ctx->mvps);
 
+	// Create and map bone matrix buffer
+	const size_t bone_matrix_buffer_size
+	    = swapchain_img_count * model.bone_count * sizeof(mat4_t);
+	create_buffer(
+	    ctx, bone_matrix_buffer_size, VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT,
+	    VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT
+	        | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT,
+	    &ctx->bone_matrix_buffer, &ctx->bone_matrix_buffer_mem);
+	vkMapMemory(
+	    ctx->dev, ctx->bone_matrix_buffer_mem, 0, bone_matrix_buffer_size, 0,
+	    (void **)&ctx->bone_matrices);
+
 	// Configure descriptor sets to use MVP buffer
 	for (unsigned i = 0; i < swapchain_img_count; ++i) {
 		const VkWriteDescriptorSet desc_write = {
@@ -803,6 +815,10 @@ void gpu_cleanup(const gpu_ctx_t *ctx)
 	vkDestroyRenderPass(ctx->dev, ctx->render_pass, nullptr);
 	vkDestroyPipelineLayout(ctx->dev, ctx->pipeline_layout, nullptr);
 
+	vkUnmapMemory(ctx->dev, ctx->bone_matrix_buffer_mem);
+	vkDestroyBuffer(ctx->dev, ctx->bone_matrix_buffer, nullptr);
+	vkFreeMemory(ctx->dev, ctx->bone_matrix_buffer_mem, nullptr);
+
 	vkUnmapMemory(ctx->dev, ctx->mvp_buffer_mem);
 	vkDestroyBuffer(ctx->dev, ctx->mvp_buffer, nullptr);
 	vkFreeMemory(ctx->dev, ctx->mvp_buffer_mem, nullptr);
diff --git a/gpu.h b/gpu.h
index fa89023..c242544 100644
--- a/gpu.h
+++ b/gpu.h
@@ -37,6 +37,9 @@ typedef struct {
 	VkBuffer mvp_buffer;
 	VkDeviceMemory mvp_buffer_mem;
 	mvp_t *mvps;
+	VkBuffer bone_matrix_buffer;
+	VkDeviceMemory bone_matrix_buffer_mem;
+	mat4_t *bone_matrices;
 	VkPipelineLayout pipeline_layout;
 	VkRenderPass render_pass;
 	VkPipeline pipeline;