cairo & cairomm example

아래의 코드들은 wxWidgets와의 조합이며, wxEVT_PAINT 이벤트내에서 작성하면 될것이다. MinGW로 테스트 되었다.

아래의 코드는 cairo의 경우이다.

wxPaintDC dc(this);

wxRect rect = GetClientRect();

if(rect.width == 0 || rect.height == 0) return;

// RENDER_NATIVE
HWND hWnd = (HWND)this->GetHandle();
HDC hDC = ::GetDC(hWnd);

HDC hMemDC = CreateCompatibleDC(hDC);
HBITMAP hBitmap = CreateCompatibleBitmap(hDC, rect.width, rect.height);
SelectObject(hMemDC, hBitmap); 

cairo_surface_t* surface = cairo_win32_surface_create(hMemDC);
cairo_t* image = cairo_create(surface);

cairo_pattern_t *pat;

pat = cairo_pattern_create_linear (0.0, 0.0,  0.0, 256.0);
cairo_pattern_add_color_stop_rgba (pat, 1, 0, 0, 0, 1);
cairo_pattern_add_color_stop_rgba (pat, 0, 1, 1, 1, 1);
cairo_rectangle (image, 0, 0, rect.width, rect.height);
cairo_set_source (image, pat);
cairo_fill (image);
cairo_pattern_destroy (pat);

pat = cairo_pattern_create_radial (115.2, 102.4, 25.6,
							   102.4,  102.4, 128.0);
cairo_pattern_add_color_stop_rgba (pat, 0, 1, 1, 1, 1);
cairo_pattern_add_color_stop_rgba (pat, 1, 0, 0, 0, 1);
cairo_set_source (image, pat);
cairo_arc (image, 128.0, 128.0, 76.8, 0, 2 * M_PI);
cairo_fill (image);
cairo_pattern_destroy (pat);

BitBlt(hDC, 0, 0, rect.width, rect.height, hMemDC, 0, 0, SRCCOPY);

DeleteDC(hMemDC);
DeleteObject(hBitmap);

// Because we called ::GetDC make sure we relase the handle
// back to the system or we'll have a memory leak.
::ReleaseDC(hWnd, hDC);

아래의 코드는 cairomm의 경우이다.

wxPaintDC dc(this);

wxRect rect = GetClientRect();

if(rect.width == 0 || rect.height == 0) return;

// RENDER_NATIVE
HWND hWnd = (HWND)this->GetHandle();
HDC hDC = ::GetDC(hWnd);

HDC hMemDC = CreateCompatibleDC(hDC);
HBITMAP hBitmap = CreateCompatibleBitmap(hDC, rect.width, rect.height);
SelectObject(hMemDC, hBitmap); 

Cairo::RefPtr<Context> context;
Cairo::RefPtr<Win32Surface> surface;

surface = Win32Surface::create(hMemDC);
context = Context::create(surface);

// draw background
Cairo::RefPtr<Cairo::LinearGradient> background_gradient_ptr = 
	Cairo::LinearGradient::create (0, 0, rect.width, rect.height);

background_gradient_ptr->add_color_stop_rgb (0, 0.7,0,0);
background_gradient_ptr->add_color_stop_rgb (1, 0.3,0,0);

// Draw a rectangle and fill with gradient
context->set_source (background_gradient_ptr);
context->rectangle (0, 0, rect.width, rect.height);
context->fill();

surface->finish();

BitBlt(hDC, 0, 0, rect.width, rect.height, hMemDC, 0, 0, SRCCOPY);

DeleteDC(hMemDC);
DeleteObject(hBitmap);

// Because we called ::GetDC make sure we relase the handle
// back to the system or we'll have a memory leak.
::ReleaseDC(hWnd, hDC);