我正在将一个工具包（即 EFL）引擎从纯 GDI 移植到 Direct2D。更准确地说，我正在添加一个 Direct2D 引擎。目的是拥有比 GDI 更快的引擎。
这个工具包是跨平台的，已经存在很长时间了，所以我不能修改它。我可以使用它提供给我的东西。
它有一个状态完整的画布。当必须绘制窗口的内容时，它会提供一个 BGRA 矩形数组（x、y、w、h 和 BGRA 数据），该数组自上一个窗口内容以来已被修改。
我已经在考虑 DirectComposition 的情况下设置了 D2D（还具有每个像素的透明度，并且 Kenny Kerr 说过它比没有直接组合的情况要快）。
天真的方法是创建一个大小为寡妇大小的位图，并保留它以供渲染。然后我执行以下步骤：
- 我遍历矩形，对于每个矩形，我调用 CopyFromMemory() 来更新位图中的每个矩形区域
- 我打电话给 BeginDraw()
- 我调用 DrawBitmap() 来渲染整个位图
- 我打电话给 EndDraw()
有用。这是完整的代码：
#define _WIN32_WINNT 0x0A00
#include <stdio.h> /* I know, not C++ stuff */
#include <windows.h>
#include <d3d11.h>
#include <dxgi1_3.h>
#include <dcomp.h>
#include <d2d1_1.h>
#define E_DEBUG 1
typedef struct
{
HINSTANCE instance;
HWND win;
} Window;
typedef struct
{
ID3D11Device *d3d_device;
IDXGIDevice *dxgi_device;
IDXGIFactory2 *dxgi_factory;
ID2D1Factory1 *d2d_factory;
ID2D1Device *d2d_device;
ID2D1DeviceContext *d2d_device_ctx;
IDCompositionDevice *dcomp_device;
IDCompositionVisual *dcomp_visual;
IDCompositionTarget *dcomp_target;
IDXGISwapChain1 *dxgi_swapchain;
} D2d;
ID2D1Bitmap1 *bitmap;
void render(D2d* d2d);
void draw(D2d* d2d);
/***************************** Window *****************************/
LRESULT CALLBACK
_window_procedure(HWND window,
UINT message,
WPARAM window_param,
LPARAM data_param)
{
switch (message)
{
case WM_CLOSE:
PostQuitMessage(0);
return 0;
case WM_KEYUP:
if (window_param == 'Q')
{
PostQuitMessage(0);
}
if (window_param == 'T')
{
printf("key 'T'\n");
fflush(stdout);
}
if (window_param == 'D')
{
D2d *d2d;
d2d = (D2d *)GetWindowLongPtr(window, GWLP_USERDATA);
printf("key 'D'\n");
fflush(stdout);
draw(d2d);
}
return 0;
/* GDI notifications */
case WM_CREATE:
return 0;
case WM_PAINT:
{
RECT rect;
printf("paint\n");
fflush(stdout);
if (GetUpdateRect(window, &rect, FALSE))
{
PAINTSTRUCT ps;
D2d *d2d = NULL;;
BeginPaint(window, &ps);
d2d = (D2d *)GetWindowLongPtr(window, GWLP_USERDATA);
render(d2d);
EndPaint(window, &ps);
}
return 0;
}
default:
return DefWindowProc(window, message, window_param, data_param);
}
}
Window *window_new(int x, int y, int w, int h)
{
WNDCLASS wc;
RECT r;
Window *win;
DWORD style;
DWORD exstyle;
win = (Window *)calloc(1, sizeof(Window));
if (!win)
return NULL;
win->instance = GetModuleHandle(NULL);
if (!win->instance)
goto free_win;
memset (&wc, 0, sizeof (WNDCLASS));
wc.style = CS_HREDRAW | CS_VREDRAW;
wc.lpfnWndProc = _window_procedure;
wc.cbClsExtra = 0;
wc.cbWndExtra = 0;
wc.hInstance = win->instance;
wc.hIcon = LoadIcon (NULL, IDI_APPLICATION);
wc.hCursor = LoadCursor (NULL, IDC_ARROW);
wc.hbrBackground = NULL;
wc.lpszMenuName = NULL;
wc.lpszClassName = "D2D";
if(!RegisterClass(&wc))
goto free_library;
style = WS_OVERLAPPEDWINDOW | WS_SIZEBOX;
exstyle = WS_EX_NOREDIRECTIONBITMAP;
r.left = 0;
r.top = 0;
r.right = w;
r.bottom = h;
if (!AdjustWindowRectEx(&r, style, FALSE, exstyle))
goto unregister_class;
win->win = CreateWindowEx(exstyle,
"D2D", "Test",
style,
x, y,
r.right - r.left,
r.bottom - r.top,
NULL,
NULL, win->instance, NULL);
if (!win->win)
goto unregister_class;
printf("win new %p\n", win);
fflush(stdout);
printf("win->win new %p\n", win->win);
fflush(stdout);
return win;
unregister_class:
UnregisterClass("D2D", win->instance);
free_library:
FreeLibrary(win->instance);
free_win:
free(win);
return NULL;
}
void window_del(Window *win)
{
if (!win)
return;
DestroyWindow(win->win);
UnregisterClass("D2D", win->instance);
FreeLibrary(win->instance);
free(win);
}
void window_show(Window *win)
{
ShowWindow(win->win, SW_SHOWNORMAL);
}
/***************************** Direct2D *****************************/
/***** helper functions for rectangles to display *****/
int rect_1(int w, int h, unsigned int **data)
{
unsigned int *d;
unsigned int *iter;
int i;
int j;
d = (unsigned int *)malloc(w * h * sizeof(unsigned int));
if (!d)
{
*data = NULL;
return 0;
}
iter = d;
for (i = 0; i < h; i++)
{
for (j = 0; j < w; j++, iter++)
{
if (i >= 50 && j >= 50)
*iter = 0xaa0000ff;
else
*iter = 0xffff0000;
}
}
*data = d;
return 1;
}
int rect_2(int w, int h, unsigned int **data)
{
unsigned int *d;
unsigned int *iter;
int i;
int j;
d = (unsigned int *)malloc(w * h * sizeof(unsigned int));
if (!d)
{
*data = NULL;
return 0;
}
iter = d;
for (i = 0; i < h; i++)
{
int g;
for (j = 0; j < w; j++, iter++)
{
g = (j * 255) / (h - 1);
*iter = (255 << 24) | (g << 8);
}
}
*data = d;
return 1;
}
int rect_3(int w, int h, unsigned int **data)
{
unsigned int *d;
unsigned int *iter;
int i;
int j;
d = (unsigned int *)malloc(w * h * sizeof(unsigned int));
if (!d)
{
*data = NULL;
return 0;
}
iter = d;
for (i = 0; i < h; i++)
{
int b;
int g;
b = (i * 255) / (w - 1);
for (j = 0; j < w; j++, iter++)
{
g = (j * 255) / (h - 1);
*iter = (255 << 24) | (g << 8) | b;
}
}
*data = d;
return 1;
}
D2d *d2d_init(Window *win)
{
const D3D_FEATURE_LEVEL levels[] =
{
D3D_FEATURE_LEVEL_12_1,
D3D_FEATURE_LEVEL_12_0,
D3D_FEATURE_LEVEL_11_1,
D3D_FEATURE_LEVEL_11_0,
D3D_FEATURE_LEVEL_10_1,
D3D_FEATURE_LEVEL_10_0
};
D2D1_FACTORY_OPTIONS opt;
DXGI_SWAP_CHAIN_DESC1 desc;
D2d *d2d;
IDXGISurface *surface;
ID2D1Bitmap1 *bmp;
RECT r;
HRESULT res;
d2d = (D2d *)calloc(1, sizeof(D2d));
if (!d2d)
return NULL;
/* direct3d device */
res = D3D11CreateDevice(NULL, D3D_DRIVER_TYPE_HARDWARE, NULL,
D3D11_CREATE_DEVICE_BGRA_SUPPORT
#if E_DEBUG
| D3D11_CREATE_DEVICE_DEBUG
#endif
,
levels, sizeof(levels) / sizeof(D3D_FEATURE_LEVEL),
D3D11_SDK_VERSION, &d2d->d3d_device, NULL, NULL);
if (FAILED(res))
goto free_d2d;
/* dxgi device */
res = d2d->d3d_device->QueryInterface(&d2d->dxgi_device);
if (FAILED(res))
goto release_d3d_device;
/* dxgi factory */
res = CreateDXGIFactory2(
#if E_DEBUG
DXGI_CREATE_FACTORY_DEBUG,
#else
0,
#endif
__uuidof(d2d->dxgi_factory),
(void **)&d2d->dxgi_factory);
if (FAILED(res))
goto release_dxgi_device;
/* d2d factory */
#if E_DEBUG
opt.debugLevel = D2D1_DEBUG_LEVEL_INFORMATION;
#else
opt.debugLevel = D2D1_DEBUG_LEVEL_NONE;
#endif
res = D2D1CreateFactory(D2D1_FACTORY_TYPE_SINGLE_THREADED,
__uuidof(d2d->d2d_factory), &opt,
(void **)&d2d->d2d_factory);
if (FAILED(res))
goto release_dxgi_factory;
/* d2d device */
res = d2d->d2d_factory->CreateDevice(d2d->dxgi_device, &d2d->d2d_device);
if (FAILED(res))
goto release_d2d_factory;
/* d2d device context */
// FIXME : D2D1_DEVICE_CONTEXT_OPTIONS_ENABLE_MULTITHREADED_OPTIMIZATIONS ?
res = d2d->d2d_device->CreateDeviceContext(D2D1_DEVICE_CONTEXT_OPTIONS_NONE,
&d2d->d2d_device_ctx);
if (FAILED(res))
goto release_d2d_device;
/* dcomp device */
res = DCompositionCreateDevice(d2d->dxgi_device,
__uuidof(d2d->dcomp_device),
(void **)&d2d->dcomp_device);
if (FAILED(res))
goto release_d2d_device_ctx;
/* dcomp visual */
res = d2d->dcomp_device->CreateVisual(&d2d->dcomp_visual);
if (FAILED(res))
goto release_dcomp_device;
/* dcomp target */
res = d2d->dcomp_device->CreateTargetForHwnd(win->win, TRUE,
&d2d->dcomp_target);
if (FAILED(res))
goto release_dcomp_visual;
/* dxgi swapchain */
if (!GetClientRect(win->win, &r))
goto release_dcomp_target;
desc.Width = r.right - r.left; /* width of client area */
desc.Height = r.bottom - r.top; /* height of client area */
desc.Format = DXGI_FORMAT_B8G8R8A8_UNORM;
desc.Stereo = FALSE;
desc.SampleDesc.Count = 1;
desc.SampleDesc.Quality = 0;
desc.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
desc.BufferCount = 2;
desc.Scaling = DXGI_SCALING_STRETCH;
desc.SwapEffect= DXGI_SWAP_EFFECT_FLIP_SEQUENTIAL;
desc.AlphaMode = DXGI_ALPHA_MODE_PREMULTIPLIED;
desc.Flags = 0;
res = d2d->dxgi_factory->CreateSwapChainForComposition(d2d->dxgi_device,
&desc,
NULL,
&d2d->dxgi_swapchain);
if (FAILED(res))
goto release_dcomp_target;
printf(" * %s : swapchain : %p %p\n", __FUNCTION__, d2d, d2d->dxgi_swapchain);
fflush(stdout);
/* swapchain buffer in a IDXGISurface */
res = d2d->dxgi_swapchain->GetBuffer(0, __uuidof(surface),
(void **)&surface);
if (FAILED(res))
goto release_dxgi_swapchain;
printf("backbuffer1\n");
res = d2d->d2d_device_ctx->CreateBitmapFromDxgiSurface(surface,
NULL,
&bmp);
if (!FAILED(res))
{
printf("backbuffer2\n");
d2d->d2d_device_ctx->SetTarget(bmp);
bmp->Release();
}
surface->Release();
return d2d;
release_dxgi_swapchain:
d2d->dxgi_swapchain->Release();
release_dcomp_target:
d2d->dcomp_target->Release();
release_dcomp_visual:
d2d->dcomp_visual->Release();
release_dcomp_device:
d2d->dcomp_device->Release();
release_d2d_device_ctx:
d2d->d2d_device_ctx->Release();
release_d2d_device:
d2d->d2d_device->Release();
release_d2d_factory:
d2d->d2d_factory->Release();
release_dxgi_factory:
d2d->dxgi_factory->Release();
release_dxgi_device:
d2d->dxgi_device->Release();
release_d3d_device:
d2d->d3d_device->Release();
free_d2d:
free(d2d);
return NULL;
}
void d2d_shutdown(D2d *d2d)
{
d2d->dxgi_swapchain->Release();
d2d->dcomp_target->Release();
d2d->dcomp_visual->Release();
d2d->dcomp_device->Release();
d2d->d2d_device_ctx->Release();
d2d->d2d_device->Release();
d2d->d2d_factory->Release();
d2d->dxgi_factory->Release();
d2d->dxgi_device->Release();
d2d->d3d_device->Release();
}
void render(D2d* d2d)
{
D2D1_BITMAP_PROPERTIES1 properties;
DXGI_SWAP_CHAIN_DESC1 desc;
D2D1_COLOR_F c;
HRESULT res;
printf(" * %s : %p\n", __FUNCTION__, d2d);
fflush(stdout);
printf(" * %s : %p\n", __FUNCTION__, d2d->dxgi_swapchain);
fflush(stdout);
// get size from swapchain (for example)
d2d->dxgi_swapchain->GetDesc1(&desc);
D2D1_SIZE_U s = { desc.Width, desc.Height };
unsigned int* data;
if (!rect_1(s.width, s.height, &data))
{
printf(" * %s malloc failed\n", __FUNCTION__);
fflush(stdout);
return;
}
// create a bitmap from properties & pixel buffer
// hint: in general for most structures, it's much easier to use ZeroMemory or memset(0) so by default values are automatically set
ZeroMemory(&properties, sizeof(properties));
properties.pixelFormat.format = desc.Format;
properties.pixelFormat.alphaMode = D2D1_ALPHA_MODE_PREMULTIPLIED;
res = d2d->d2d_device_ctx->CreateBitmap(s, data, 4 * s.width, properties, &bitmap);
if (FAILED(res))
{
printf(" * %s CreateBitmap failed\n", __FUNCTION__);
fflush(stdout);
goto data_free;
}
d2d->d2d_device_ctx->BeginDraw();
c.r = 0.0f;
c.g = 0.0f;
c.b = 0.0f;
c.a = 0.0f;
d2d->d2d_device_ctx->Clear(&c);
D2D1_RECT_F rect;
rect.left = 0.0f;
rect.top = 0.0f;
rect.right = (float)s.width;
rect.bottom = (float)s.height;
d2d->d2d_device_ctx->DrawBitmap(bitmap, rect, 1.0f, D2D1_BITMAP_INTERPOLATION_MODE_LINEAR, rect);
d2d->d2d_device_ctx->EndDraw(NULL, NULL);
d2d->dxgi_swapchain->Present(1, 0);
d2d->dcomp_visual->SetContent(d2d->dxgi_swapchain);
d2d->dcomp_target->SetRoot(d2d->dcomp_visual);
d2d->dcomp_device->Commit();
data_free:
free(data);
}
void draw(D2d *d2d)
{
D2D1_RECT_U r;
unsigned int *data;
int x, y, w, h;
x = 10;
y = 10;
w = 100;
h = 100;
if (!rect_2(w, h, &data))
{
printf("rect_2 failed\n");
return;
}
r.left = x;
r.top= y;
r.right = x + w - 1;
r.bottom = y + h - 1;
bitmap->CopyFromMemory(&r, data, 4 * w);
x = 150;
y = 150;
w = 100;
h = 100;
if (!rect_3(w, h, &data))
{
printf("rect_2 failed\n");
return;
}
r.left = x;
r.top= y;
r.right = x + w - 1;
r.bottom = y + h - 1;
bitmap->CopyFromMemory(&r, data, 4 * w);
d2d->d2d_device_ctx->BeginDraw();
D2D1_RECT_F rect;
rect.left = 0.0f;
rect.top = 0.0f;
rect.right = (float)640;
rect.bottom = (float)480;
d2d->d2d_device_ctx->DrawBitmap(bitmap, rect, 1.0f,
D2D1_BITMAP_INTERPOLATION_MODE_LINEAR, rect);
d2d->d2d_device_ctx->EndDraw(NULL, NULL);
d2d->dxgi_swapchain->Present(1, 0);
d2d->dcomp_visual->SetContent(d2d->dxgi_swapchain);
d2d->dcomp_target->SetRoot(d2d->dcomp_visual);
d2d->dcomp_device->Commit();
}
/***************************** main *****************************/
int main()
{
Window *win;
D2d *d2d;
win = window_new(100, 100, 640, 480);
if (!win)
return 1;
d2d = d2d_init(win);
if (!d2d)
goto win_del;
SetWindowLongPtr(win->win, GWLP_USERDATA, (LONG_PTR)d2d);
window_show(win);
/* msg loop */
while(1)
{
MSG msg;
BOOL ret;
ret = PeekMessage(&msg, NULL, 0, 0, PM_REMOVE);
if (ret)
{
do
{
if (msg.message == WM_QUIT)
goto beach;
TranslateMessage(&msg);
DispatchMessageW(&msg);
} while (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE));
}
}
beach:
d2d_shutdown(d2d);
win_del:
window_del(win);
return 0;
}
该代码的第一部分是创建和销毁窗口，第二部分处理 Direct2D。函数 render() 渲染背景。函数 draw() 呈现 2 个 BGRA 矩形（实际上是正方形......）。
我的问题：有没有比调用多次 CopyFromMemory() 更快的方法，比如在我的 draw() 函数中，来实现这一点？
谢谢你