Various improvements

- Support static linking
- Buffer manager

meson.build

@@ -1,5 +1,5 @@
 project('voyage', 'c',
-  default_options: ['buildtype=debugoptimized', 'b_sanitize=address', 'c_std=c17', 'warning_level=3'])
+  default_options: ['buildtype=debug', 'b_sanitize=address', 'c_std=c17', 'warning_level=3'])
 
 compiler = meson.get_compiler('c')
 buildtype = get_option('buildtype')
@@ -21,6 +21,10 @@ elif compiler.get_argument_syntax() == 'msvc'
   endif
 endif
 
+if get_option('default_library') == 'static'
+    add_project_arguments(['-DVY_STATIC_LIB'], language : 'c')
+endif
+
 # Debug specific flags
 if buildtype == 'debug' or buildtype == 'debugoptimized'
   add_project_arguments([ '-DVY_DEBUG'], language : 'c')
@@ -51,6 +55,7 @@ runtime_lib = library('vyrt',
   'src/runtime/jobs.h',
   'src/runtime/aio.h',
   'src/runtime/file_tab.h',
+  'src/runtime/buffer_manager.h',
 
   'src/runtime/error_report.c',
   'src/runtime/gfx_main.c',
@@ -65,6 +70,7 @@ runtime_lib = library('vyrt',
   'src/runtime/jobs.c',
   'src/runtime/aio.c',
   'src/runtime/file_tab.c',
+  'src/runtime/buffer_manager.c',
 
   # Contrib Sources
   'contrib/xxhash/xxhash.c',
@@ -72,6 +78,10 @@ runtime_lib = library('vyrt',
   include_directories : incdir,
   c_pch : 'pch/rt_pch.h')
 
+
+# Renderer libraries
+static_renderer_lib = 'NONE'
+
 if vk_dep.found()
   platform_defs = []
   if get_option('use_xlib')
@@ -98,12 +108,22 @@ if vk_dep.found()
     link_with : [runtime_lib],
     c_pch : 'pch/vk_pch.h',
     c_args : platform_defs)
+
+  static_renderer_lib = vk_renderer_lib
+endif
+
+
+game_link_libs = []
+if get_option('default_library') == 'static'
+  game_link_libs = [runtime_lib, static_renderer_lib]
+else
+  game_link_libs = [runtime_lib]
 endif
 
 executable('voyage',
   'src/game/voyage.c',
   include_directories : incdir,
-  link_with : [runtime_lib],
+  link_with : game_link_libs,
   win_subsystem : 'windows')
 
 

src/renderer/vk/gfx_pipelines.c

@@ -52,8 +52,7 @@ static void ReleasePipelineSlot(vy_gfx_pipeline_handle id) {
         _storage.generation_in_use[slot] &= ~0x1;
 }
 
-VY_DLLEXPORT vy_gfx_pipeline_handle
+vy_gfx_pipeline_handle VY_RENDERER_API_FN(CompileComputePipeline)(const vy_compute_pipeline_info *info) {
-vyCompileComputePipeline(const vy_compute_pipeline_info *info) {
 #if 0
     char info_log[512];
 
@@ -94,8 +93,7 @@ vyCompileComputePipeline(const vy_compute_pipeline_info *info) {
     return StorePipeline(pipeline);
 }
 
-VY_DLLEXPORT vy_gfx_pipeline_handle
+vy_gfx_pipeline_handle VY_RENDERER_API_FN(CompileGraphicsPipeline)(const vy_graphics_pipeline_info *info) {
-vyCompileGraphicsPipeline(const vy_graphics_pipeline_info *info) {
 
 #if 0
     char info_log[512];

src/renderer/vk/init.c

@@ -85,7 +85,7 @@ DebugUtilsMessengerCb(VkDebugUtilsMessageSeverityFlagBitsEXT severity,
 extern vy_cvar r_VkPreferredSwapchainImages;
 extern vy_cvar r_VkPreferMailboxMode;
 
-VY_DLLEXPORT void vyRegisterCVars(void) {
+void VY_RENDERER_API_FN(RegisterCVars)(void) {
     vyRegisterCVAR(&r_VkEnableAPIAllocTracking);
     vyRegisterCVAR(&r_VkPhysDeviceName);
     vyRegisterCVAR(&r_VkPreferredSwapchainImages);
@@ -470,7 +470,7 @@ static vy_result CreateDevice(void) {
     return VY_SUCCESS;
 }
 
-VY_DLLEXPORT vy_result vyInit(const vy_renderer_init_info *info) {
+vy_result VY_RENDERER_API_FN(Init)(const vy_renderer_init_info *info) {
     vyLog("vk", "Init");
 
     _tracking_alloc_cbs.pUserData       = NULL;
@@ -503,7 +503,7 @@ VY_DLLEXPORT vy_result vyInit(const vy_renderer_init_info *info) {
     return VY_SUCCESS;
 }
 
-VY_DLLEXPORT void vyShutdown(void) {
+void VY_RENDERER_API_FN(Shutdown)(void) {
     vyLog("vk", "Shutdown");
     vkDeviceWaitIdle(g_gpu.device);
     vyDestroySwapchain();

src/runtime/app.c

@@ -3,6 +3,7 @@
 #include "gfx.h"
 #include "aio.h"
 #include "renderer_api.h"
+#include "buffer_manager.h"
 
 extern void __RegisterRuntimeCVars(void);
 
@@ -37,6 +38,11 @@ VY_DLLEXPORT int vyWin32Entry(HINSTANCE hInstance,
 
     /* TODO: Parse the cvar config file */
 
+    if (vyInitBufferManager() != VY_SUCCESS) {
+        vyReportError("BUFFERMGR", "Init failed.");
+        return 1;
+    }
+
     if (vyInitFileTab(1024) != VY_SUCCESS) {
         vyReportError("FTAB", "Init failed.");
         return 1;
@@ -131,6 +137,7 @@ VY_DLLEXPORT int vyWin32Entry(HINSTANCE hInstance,
     vyShutdownAIO();
     vyShutdownAIO();
     vyShutdownFileTab();
+    vyShutdownBufferManager();
 
     return 0;
 }
@@ -180,6 +187,11 @@ VY_DLLEXPORT int vyXlibEntry(int argc, char **argv) {
     __RegisterRuntimeCVars();
     vyRegisterRendererCVars();
 
+    if (vyInitBufferManager() != VY_SUCCESS) {
+        vyReportError("BUFFERMGR", "Init failed.");
+        return 1;
+    }
+
     if (vyInitFileTab(1024) != VY_SUCCESS) {
         vyReportError("FTAB", "Init failed.");
         return 1;
@@ -260,6 +272,7 @@ VY_DLLEXPORT int vyXlibEntry(int argc, char **argv) {
     XCloseDisplay(dpy);
     vyShutdownAIO();
     vyShutdownFileTab();
+    vyShutdownBufferManager();
 
     return 0;
 }

src/runtime/buffer_manager.c

@@ -0,0 +1,250 @@
+#include "runtime.h"
+#include "threading.h"
+#include "config.h"
+#include "buffer_manager.h"
+
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <assert.h>
+
+typedef struct vy_buffer_region_s {
+    void *memory;
+    int16_t *refcounts; // One per block
+    uint32_t *bitmap;
+    size_t block_count;
+    vy_mutex *guard;
+} vy_buffer_region;
+
+/* Count leading zeroes.
+ * Note that the return value of __builtin_clz(0) is undefined. */
+#ifdef _MSC_VER
+
+#include <intrin.h>
+
+#define lzcnt32(x) __lzcnt((x))
+#define popcnt32(x) __popcnt((x))
+
+static __forceinline uint32_t tzcnt32(uint32_t x) {
+    unsigned long i;
+    _BitScanForward(&i, x);
+    return (uint32_t)i;
+}
+
+static inline bool IsLZCNTSupported(void) {
+#define Type 0x80000001
+    int info[4];
+    __cpuid(info, Type);
+    return (info[2] & (1 << 5)) != 0;
+#undef Type
+}
+
+#elif defined(__GNUC__)
+#define lzcnt32(x) __builtin_clz((x))
+#define tzcnt32(x)  __builtin_ctz((x))
+#define popcnt32(x) __builtin_popcount((x))
+
+#define IsLZCNTSupported() true
+
+#endif
+
+/* NOTE(Kevin): Keep these sorted! */
+static size_t _block_sizes[] = {VY_KB(512), VY_MB(1), VY_MB(4), VY_MB(8) };
+#define NUM_BLOCK_SIZES (sizeof(_block_sizes) / sizeof(_block_sizes[0]))
+static vy_buffer_region _regions[NUM_BLOCK_SIZES];
+
+VY_CVAR_SZ(
+    rt_BufferManagerMemory,
+    "Total number of bytes allocated for the buffer manager. Default: 1GB", VY_GB(1));
+
+VY_DLLEXPORT vy_result vyInitBufferManager(void) {
+    if ((rt_BufferManagerMemory.sz % NUM_BLOCK_SIZES) != 0)
+        vyLog("BUFFERMGR",
+              "Configured memory amount is not dividable by number of block "
+              "sizes: %u MB/%u",
+              rt_BufferManagerMemory.sz / (1024 * 1024),
+              NUM_BLOCK_SIZES);
+
+    size_t mem_per_size = rt_BufferManagerMemory.sz / NUM_BLOCK_SIZES;
+    for (unsigned int i = 0; i < NUM_BLOCK_SIZES; ++i) {
+        if ((mem_per_size % _block_sizes[i]) != 0)
+            vyLog("BUFFERMGR",
+                  "Memory per block size is not dividable by block size: %u "
+                  "MB/%u KB",
+                  mem_per_size / (1024 * 1024),
+                  _block_sizes[i] / 1024);
+
+        size_t block_count = mem_per_size / _block_sizes[i];
+        _regions[i].block_count = block_count;
+        _regions[i].guard       = vyCreateMutex();
+        if (!_regions[i].guard) {
+            vyReportError("BUFFERMGR", "Failed to create guard mutex %u", i);
+            return VY_BUFFER_MGR_MUTEX_CREATION_FAILED;
+        }
+        _regions[i].memory      = malloc(mem_per_size);
+        if (!_regions[i].memory) {
+            vyDestroyMutex(_regions[i].guard);
+            vyReportError("BUFFERMGR", "Failed to allocate memory.", i);
+            return VY_BUFFER_MGR_OUT_OF_MEMORY;
+        }
+        _regions[i].bitmap = calloc((block_count + 31) / 32, sizeof(uint32_t));
+        if (!_regions[i].bitmap) {
+            vyDestroyMutex(_regions[i].guard);
+            free(_regions[i].memory);
+            vyReportError("BUFFERMGR", "Failed to allocate memory.", i);
+            return VY_BUFFER_MGR_OUT_OF_MEMORY;
+        }
+        _regions[i].refcounts = calloc(block_count, sizeof(uint16_t));
+        if (!_regions[i].refcounts) {
+            vyDestroyMutex(_regions[i].guard);
+            free(_regions[i].memory);
+            free(_regions[i].bitmap);
+            vyReportError("BUFFERMGR", "Failed to allocate memory.", i);
+            return VY_BUFFER_MGR_OUT_OF_MEMORY;
+        }
+    }
+    return VY_SUCCESS;
+}
+
+VY_DLLEXPORT void vyShutdownBufferManager(void) {
+    for (unsigned int i = 0; i < NUM_BLOCK_SIZES; ++i) {
+        vyDestroyMutex(_regions[i].guard);
+        free(_regions[i].memory);
+        free(_regions[i].bitmap);
+        free(_regions[i].refcounts);
+    }
+}
+
+VY_DLLEXPORT void *vyAllocBuffer(size_t size) {
+    assert(IsLZCNTSupported());
+    
+    // Determine the best block size to use
+    size_t required_blocks = (size + _block_sizes[0] - 1) / _block_sizes[0];
+    size_t best_fit        = 0;
+    for (size_t i = 1; i < NUM_BLOCK_SIZES; ++i) {
+        size_t block_count = (size + _block_sizes[i] - 1) / _block_sizes[i];
+        if (block_count < required_blocks && size >= _block_sizes[i]) {
+            required_blocks = block_count;
+            best_fit        = i;
+        }
+    }
+
+    void *result = NULL;
+
+    vy_buffer_region *region = &_regions[best_fit];
+    vyLockMutex(region->guard);
+    size_t dword_count = (region->block_count + 31) / 32;
+
+    if (required_blocks < 32) {
+        /* Fast path for allocations that potentially fit into one dword */
+        uint32_t in_use_mask = (1ull << required_blocks) - 1;
+        size_t max_occupancy = 32 - required_blocks;
+        for (size_t i = 0; i < dword_count; ++i) {
+            size_t block_index = 0;
+            if (region->bitmap[i] != 0 && popcnt32(region->bitmap[i]) < max_occupancy) {
+                size_t free_high_blocks = lzcnt32(region->bitmap[i]);
+                if (free_high_blocks >= required_blocks) {
+                    /* High blocks are free */
+                    size_t first_free = 32 - free_high_blocks;
+                    region->bitmap[i] |= (in_use_mask << first_free);
+                    block_index = i * 32 + first_free;
+                    result      = (char *)region->memory +
+                        block_index * _block_sizes[best_fit];
+                } else if (tzcnt32(region->bitmap[i]) >= required_blocks) {
+                    /* Low blocks are free */
+                    region->bitmap[i] |= in_use_mask;
+                    block_index = i * 32;
+                    result      = (char *)region->memory +  block_index * _block_sizes[best_fit];
+                } else {
+                    /* Check if we can find a large enough range of free blocks.
+                     * Start after the first set bit.
+                     */
+                    for (uint32_t j = tzcnt32(region->bitmap[i]) + 1; j < 32 - required_blocks; ++j) {
+                        if ((region->bitmap[i] & in_use_mask << j) == 0) {
+                            region->bitmap[i] |= (in_use_mask << j);
+                            block_index = i * 32 + j;
+                            result = (char *)region->memory + block_index * _block_sizes[best_fit];
+                            break;
+                        }
+                    }
+                }
+            } else if (region->bitmap[i] == 0) {
+                /* All free */
+                region->bitmap[i]  = in_use_mask;
+                block_index = i * 32;
+                result             = (char *)region->memory + block_index * _block_sizes[best_fit];
+            } else if (i < dword_count - 1) {
+                /* Check if we can use high blocks from this dword and low blocks from the next one */
+                size_t high_blocks = lzcnt32(region->bitmap[i]);
+                size_t low_blocks  = (region->bitmap[i + 1] != 0) ? tzcnt32(region->bitmap[i + 1]) : 32;
+
+                if (high_blocks + low_blocks >= required_blocks) {
+                    size_t high_mask = (1u << high_blocks) - 1;
+                    size_t first_free = 32 - high_blocks;
+                    size_t low_mask = (1u << (required_blocks - high_blocks)) - 1;
+                    
+                    region->bitmap[i] |= (high_mask << first_free);
+                    region->bitmap[i + 1] |= low_mask;
+                    block_index = i * 32 + first_free;
+                    result             = (char *)region->memory + block_index * _block_sizes[best_fit];
+                }
+            }
+
+            if (result) {
+                for (size_t j = 0; j < required_blocks; ++j)
+                    region->refcounts[block_index + j] = 1;
+                break;
+            }
+        }
+    }
+    vyUnlockMutex(region->guard);
+    return result;
+}
+
+VY_DLLEXPORT void vyReleaseBuffer(const void *begin, size_t size) {
+    uintptr_t begin_addr = (uintptr_t)begin;
+    for (unsigned int i = 0; i < NUM_BLOCK_SIZES; ++i) {
+        uintptr_t region_addr = (uintptr_t)_regions[i].memory;
+        size_t region_size    = _block_sizes[i] * _regions[i].block_count;
+        if (begin_addr >= region_addr &&
+                begin_addr + size <= region_addr + region_size) {
+        
+            size_t block_count = (size + _block_sizes[i] - 1) / _block_sizes[i];
+            size_t first_block = (begin_addr - region_addr) / _block_sizes[i];
+
+            vyLockMutex(_regions[i].guard);
+            for (size_t j = 0; j < block_count; ++j) {
+                size_t dword = (first_block + j) / 32;
+                size_t bit   = (first_block + j) % 32;
+
+                if (--_regions[i].refcounts[first_block + j] == 0)
+                    _regions[i].bitmap[dword] &= ~(1u << bit);
+            }
+            vyUnlockMutex(_regions[i].guard);
+            return;
+        }
+    }
+    vyLog("BUFFERMGR", "Tried to release an invalid buffer");
+}
+
+VY_DLLEXPORT void vyIncreaseBufferRefCount(const void *begin, size_t size) {
+    uintptr_t begin_addr = (uintptr_t)begin;
+    for (unsigned int i = 0; i < NUM_BLOCK_SIZES; ++i) {
+        uintptr_t region_addr = (uintptr_t)_regions[i].memory;
+        size_t region_size    = _block_sizes[i] * _regions[i].block_count;
+        if (begin_addr >= region_addr &&
+            begin_addr + size <= region_addr + region_size) {
+
+            size_t block_count = (size + _block_sizes[i] - 1) / _block_sizes[i];
+            size_t first_block = (begin_addr - region_addr) / _block_sizes[i];
+
+            vyLockMutex(_regions[i].guard);
+            for (size_t j = 0; j < block_count; ++j) {
+                ++_regions[i].refcounts[first_block + j];
+            }
+            vyUnlockMutex(_regions[i].guard);
+            return;
+        }
+    }
+    vyLog("BUFFERMGR", "Tried to increase the refcount of an invalid buffer");
+}

src/runtime/buffer_manager.h

@@ -0,0 +1,21 @@
+#ifndef VY_BUFFER_MANAGER_H
+#define VY_BUFFER_MANAGER_H
+
+#include "runtime.h"
+
+enum {
+    VY_BUFFER_MGR_OUT_OF_MEMORY = VY_SUCCESS + 1,
+    VY_BUFFER_MGR_MUTEX_CREATION_FAILED,
+};
+
+VY_DLLEXPORT vy_result vyInitBufferManager(void);
+
+VY_DLLEXPORT void vyShutdownBufferManager(void);
+
+VY_DLLEXPORT void *vyAllocBuffer(size_t size);
+
+VY_DLLEXPORT void vyReleaseBuffer(const void *begin, size_t size);
+
+VY_DLLEXPORT void vyIncreaseBufferRefCount(const void *begin, size_t size);
+
+#endif

src/runtime/config.h

@@ -8,6 +8,7 @@ typedef enum
     VY_CVAR_TYPE_INT,
     VY_CVAR_TYPE_FLOAT,
     VY_CVAR_TYPE_STRING,
+    VY_CVAR_TYPE_SIZE,
 } vy_cvar_type;
 
 typedef struct
@@ -18,6 +19,7 @@ typedef struct
         int i;
         float f;
         const char *s;
+        size_t sz;
     };
     vy_cvar_type type;
 } vy_cvar;
@@ -37,6 +39,11 @@ typedef struct
                  .description = d,                                             \
                  .s           = (v),                                           \
                  .type        = VY_CVAR_TYPE_STRING}
+#define VY_CVAR_SZ(n, d, v)                                                     \
+    vy_cvar n = {.name        = #n,                                            \
+                 .description = d,                                             \
+                 .sz          = (v),                                           \
+                 .type        = VY_CVAR_TYPE_SIZE}
 
 VY_DLLEXPORT void vyRegisterCVAR(vy_cvar *cvar);
 

src/runtime/dynamic_libs.c

@@ -4,6 +4,10 @@
 #define WIN32_LEAN_AND_MEAN
 #include <Windows.h>
 
+VY_DLLEXPORT vy_dynlib vyOpenCallerLib(void) {
+    return (vy_dynlib)GetModuleHandleW(NULL);
+}
+
 VY_DLLEXPORT vy_dynlib vyOpenLib(const char *libname) {
     wchar_t libname_w[MAX_PATH];
     MultiByteToWideChar(CP_UTF8,
@@ -27,6 +31,10 @@ VY_DLLEXPORT void vyCloseLib(vy_dynlib lib) {
 #elif defined(__linux__)
 #include <dlfcn.h>
 
+VY_DLLEXPORT vy_dynlib vyOpenCallerLib(void) {
+    return dlopen(NULL, RTLD_NOW | RTLD_LOCAL);
+}
+
 VY_DLLEXPORT vy_dynlib vyOpenLib(const char *libname) {
     return dlopen(libname, RTLD_NOW | RTLD_LOCAL);
 }

src/runtime/dynamic_libs.h

@@ -17,6 +17,8 @@ typedef void *vy_dynlib;
 
 VY_DLLEXPORT vy_dynlib vyOpenLib(const char *libname);
 
+VY_DLLEXPORT vy_dynlib vyOpenCallerLib(void);
+
 VY_DLLEXPORT void *vyGetSymbol(vy_dynlib lib, const char *symbol);
 
 VY_DLLEXPORT void vyCloseLib(vy_dynlib lib);

src/runtime/gfx_main.c

@@ -24,9 +24,21 @@ VY_CVAR_S(rt_Renderer,
 extern bool
 vyLoadShaders(const char **paths, vy_shader *shaders, unsigned int count);
 
+#ifdef VY_STATIC_LIB
+extern void VY_RENDERER_API_FN(RegisterCVars)(void);
+extern vy_result VY_RENDERER_API_FN(Init)(const vy_renderer_init_info *);
+extern void VY_RENDERER_API_FN(Shutdown)(void);
+extern vy_gfx_pipeline_handle VY_RENDERER_API_FN(CompileComputePipeline)(
+    const vy_compute_pipeline_info *);
+extern vy_gfx_pipeline_handle VY_RENDERER_API_FN(CompileGraphicsPipeline)(
+    const vy_graphics_pipeline_info *);
+#endif
+
 static bool LoadRenderer(void) {
+
+#if !defined(VY_STATIC_LIB)
     #define RETRIEVE_SYMBOL(name, type)                                        \
-    g_renderer.name = (type *)vyGetSymbol(_renderer_lib, "vy" #name);          \
+        g_renderer.name = (type *)vyGetSymbol(_renderer_lib, "vyRen" #name);   \
         if (!g_renderer.name) {                                                \
             vyReportError(                                                     \
                 "GFX",                                                         \
@@ -49,7 +61,6 @@ static bool LoadRenderer(void) {
         RETRIEVE_SYMBOL(CompileComputePipeline, vy_compile_compute_pipeline_fn);
         RETRIEVE_SYMBOL(CompileGraphicsPipeline,
                         vy_compile_graphics_pipeline_fn);
-        return true;
     } else {
         vyReportError("GFX",
                       "Unsupported renderer backend: (%s) %s",
@@ -58,6 +69,14 @@ static bool LoadRenderer(void) {
         return false;
     }
     #undef RETRIEVE_SYMBOL
+#else
+    g_renderer.RegisterCVars = &vyRenRegisterCVars;
+    g_renderer.Init          = &vyRenInit;
+    g_renderer.Shutdown      = &vyRenShutdown;
+    g_renderer.CompileComputePipeline = &vyRenCompileComputePipeline;
+    g_renderer.CompileGraphicsPipeline = &vyRenCompileGraphicsPipeline;
+#endif
+    return true;
 }
 
 VY_DLLEXPORT void vyRegisterRendererCVars(void) {

src/runtime/gfx_shader_loading.c

@@ -1,3 +1,8 @@
+/* TODO(Kevin):
+ * This should move into a standalone tool.
+ */
+
+
 #include <assert.h>
 #include <limits.h>
 #include <stdbool.h>

src/runtime/renderer_api.h

@@ -54,6 +54,8 @@ typedef struct {
     vy_compile_graphics_pipeline_fn *CompileGraphicsPipeline;
 } vy_renderer_api;
 
+#define VY_RENDERER_API_FN(name) VY_DLLEXPORT vyRen##name
+
 #ifndef VY_DONT_DEFINE_RENDERER_GLOBAL
 extern vy_renderer_api g_renderer;
 #endif

src/runtime/runtime.h

@@ -5,7 +5,7 @@
 
 #include <stddef.h>
 
-#ifdef _WIN32
+#if defined(_WIN32)
     #define VY_DLLEXPORT __declspec(dllexport)
 #else
     #define VY_DLLEXPORT
@@ -14,6 +14,10 @@
 #define VY_UNUSED(x)      ((void)sizeof((x)))
 #define VY_ARRAY_COUNT(x) (sizeof((x)) / sizeof((x)[0]))
 
+#define VY_KB(n) ((n) * 1024U)
+#define VY_MB(n) ((n) * 1024U * 1024U)
+#define VY_GB(n) ((n) * 1024U * 1024U * 1024U)
+
 typedef unsigned int vy_result;
 #define VY_SUCCESS 0
 

src/runtime/runtime_cvars.c

@@ -4,6 +4,7 @@ extern vy_cvar rt_Renderer;
 extern vy_cvar rt_Fullscreen;
 extern vy_cvar rt_WindowWidth;
 extern vy_cvar rt_WindowHeight;
+extern vy_cvar rt_BufferManagerMemory;
 
 void __RegisterRuntimeCVars(void)
 {
@@ -11,4 +12,5 @@ void __RegisterRuntimeCVars(void)
     vyRegisterCVAR(&rt_Fullscreen);
     vyRegisterCVAR(&rt_WindowWidth);
     vyRegisterCVAR(&rt_WindowHeight);
+    vyRegisterCVAR(&rt_BufferManagerMemory);
 }