- add windows example (draw in a window)

2 files changed, 251 insertions, 0 deletions

diff --git a/examples/CMakeLists.txt b/examples/CMakeLists.txt
index 468ccce..ed84fcb 100644
--- a/examples/CMakeLists.txt
+++ b/examples/CMakeLists.txt
@@ -8,6 +8,12 @@ SET(TESTS_FILES
   nnquant
 )
 
+if (WIN32)
+	SET(TESTS_FILES
+		"${TESTS_FILES}"
+		windows
+	)
+endif (WIN32)
 if (JPEG_FOUND)
 	SET(TESTS_FILES
 		"${TESTS_FILES}"
diff --git a/examples/windows.c b/examples/windows.c
new file mode 100644
index 0000000..8f7069b
--- /dev/null
+++ b/examples/windows.c
@@ -0,0 +1,245 @@
+/*
+Sample usage of GD on windows. This little program opens a window, fetch its DIB 
+and assigns to a GD truecolor image.
+
+Thanks to Mateusz Loskot (http://mateusz.loskot.net) for the AttachBuffer function!
+*/
+#include <gd.h>
+#include <windows.h>
+#include <gdfontg.h>
+#include <gdfontl.h>
+#include <windef.h>
+
+const char g_szClassName[] = "myWindowClass";
+
+gdImagePtr gdImageTrueColorAttachBuffer(int* buffer, int sx, int sy, int stride)
+{
+	int i;
+	int height;
+	int* rowptr;
+	gdImagePtr im;
+	im = (gdImage *) malloc (sizeof (gdImage));
+	if (!im) {
+		return 0;
+	}
+	memset (im, 0, sizeof (gdImage));
+#if 0
+	if (overflow2(sizeof (int *), sy)) {
+		return 0;
+	}
+#endif
+
+	im->tpixels = (int **) malloc (sizeof (int *) * sy);
+	if (!im->tpixels) {
+		free(im);
+		return 0;
+	}
+
+	im->polyInts = 0;
+	im->polyAllocated = 0;
+	im->brush = 0;
+	im->tile = 0;
+	im->style = 0;
+
+	height = sy;
+	rowptr = buffer;
+	if (stride < 0) {
+		 int startoff = (height - 1) * stride;
+		 rowptr = buffer - startoff;
+	}
+
+	i = 0;
+	while (height--) {
+		 im->tpixels[i] = rowptr;
+		 rowptr += stride;
+		 i++;
+	}
+
+	im->sx = sx;
+	im->sy = sy;
+	im->transparent = (-1);
+	im->interlace = 0;
+	im->trueColor = 1;
+	im->saveAlphaFlag = 0;
+	im->alphaBlendingFlag = 1;
+	im->thick = 1;
+	im->AA = 0;
+	im->cx1 = 0;
+	im->cy1 = 0;
+	im->cx2 = im->sx - 1;
+	im->cy2 = im->sy - 1;
+	return im;
+}
+
+
+void gdWin32Paint(HWND hwnd)
+{
+	PAINTSTRUCT ps;
+	HDC dc;
+	RECT rc;
+	int width, height;
+	BITMAPINFO bmp_info;
+	HDC mem_dc;
+	void* bits;
+	HBITMAP bmp, temp;
+	int white, black, blue, red;
+	int stride;
+	char *s = "Hello world!";
+	gdImagePtr im;
+	gdFontPtr lfont, gfont;
+
+	memset(&ps, 0, sizeof(ps));
+	dc = BeginPaint(hwnd, &ps);
+
+	GetClientRect(hwnd, &rc);
+
+	width = rc.right - rc.left;
+	height = rc.bottom - rc.top;
+
+	// Configure bitmap properties
+
+	ZeroMemory(&bmp_info, sizeof(BITMAPINFO));
+	bmp_info.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
+	bmp_info.bmiHeader.biWidth = width;
+	bmp_info.bmiHeader.biHeight = height;
+	bmp_info.bmiHeader.biPlanes = 1;
+	bmp_info.bmiHeader.biBitCount = 32;
+	bmp_info.bmiHeader.biCompression = BI_RGB;
+	bmp_info.bmiHeader.biSizeImage = 0;
+	bmp_info.bmiHeader.biXPelsPerMeter = 0;
+	bmp_info.bmiHeader.biYPelsPerMeter = 0;
+	bmp_info.bmiHeader.biClrUsed = 0;
+	bmp_info.bmiHeader.biClrImportant = 0;
+
+	// Create memory device context
+	mem_dc = CreateCompatibleDC(dc);
+	if (!mem_dc) {
+		MessageBox(NULL, "Can't create a compatible DC!", "Error!", MB_ICONEXCLAMATION | MB_OK);
+		return;
+	}
+
+	// bits points to a shared buffer of pixels
+	bits = NULL;
+	bmp = CreateDIBSection(mem_dc, &bmp_info, DIB_RGB_COLORS, (void**)&bits, 0, 0);
+
+	// Selecting the object before doing anything allows you to use libgd
+	// together with native Windows GDI.
+	temp = (HBITMAP)SelectObject(mem_dc, bmp);
+
+
+	// Start of GD drawing
+	stride = ((width * 1 + 3) >> 2) << 2;
+
+	im = NULL;
+
+	// Attach shared buffer of pixels to GD image
+	// Negative stride places 0,0 in upper-left corner
+	im = gdImageTrueColorAttachBuffer((int*)bits, width, height, -stride);
+	if (!im) {
+		MessageBox(NULL, "GD image creation failed!", "Error!", MB_ICONEXCLAMATION | MB_OK);
+		return;
+	}
+
+	white = gdImageColorAllocate(im, 255, 255, 255);
+	black = gdImageColorAllocate(im, 0, 0, 0);
+	blue = gdImageColorAllocate(im, 0, 0, 255);
+	// Allocate the color red, 50% transparent.
+	red = gdImageColorAllocateAlpha(im, 255, 0, 0, 64);
+
+	// Erase background with white color
+	gdImageFilledRectangle(im, 0, 0, width, height, 0xFF0000);
+
+	lfont = gdFontGetLarge();
+	gfont = gdFontGetGiant();
+
+	// Draw a dashed line from the upper left corner to the lower right corner.
+	gdImageFilledRectangle(im, 25, 25, 100, 100, blue);
+	gdImageChar(im, gfont, 35, 35, 'Q', white);
+	gdImageFilledRectangle(im, 50, 50, 75, 175, red);
+	gdImageLine(im, 0, 0, 150, 150, black);
+
+	gdImageString(im, gdFontGetLarge(),
+	im->sx / 2 - (strlen(s) * lfont->w / 2),
+	im->sy / 2 - lfont->h / 2,
+	(unsigned char*)s, black);
+
+
+	// Copy drawing from memory context (shared bitmap buffer) to screen DC.
+	BitBlt(dc, rc.left, rc.top, width, height, mem_dc, 0, 0, SRCCOPY);
+
+	// Free
+	//gdImageDetachBuffer(im);
+	SelectObject(mem_dc, temp);
+	DeleteObject(bmp);
+	DeleteObject(mem_dc);
+	EndPaint(hwnd, &ps);
+}
+
+// Step 4: the Window Procedure
+LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) {
+	switch(msg) {
+		case WM_PAINT:
+			gdWin32Paint(hwnd);
+				break;
+		case WM_CLOSE:
+			DestroyWindow(hwnd);
+		break;
+		case WM_DESTROY:
+			PostQuitMessage(0);
+		break;
+	default:
+		return DefWindowProc(hwnd, msg, wParam, lParam);
+	}
+	return 0;
+}
+
+int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
+    LPSTR lpCmdLine, int nCmdShow)
+{
+	WNDCLASSEX wc;
+	HWND hwnd;
+	MSG Msg;
+
+	//Step 1: Registering the Window Class
+	wc.cbSize        = sizeof(WNDCLASSEX);
+	wc.style         = 0;
+	wc.lpfnWndProc   = WndProc;
+	wc.cbClsExtra    = 0;
+	wc.cbWndExtra    = 0;
+	wc.hInstance     = hInstance;
+	wc.hIcon         = LoadIcon(NULL, IDI_APPLICATION);
+	wc.hCursor       = LoadCursor(NULL, IDC_ARROW);
+	wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
+	wc.lpszMenuName  = NULL;
+	wc.lpszClassName = g_szClassName;
+	wc.hIconSm       = LoadIcon(NULL, IDI_APPLICATION);
+
+	if(!RegisterClassEx(&wc)) {
+		MessageBox(NULL, "Window Registration Failed!", "Error!", MB_ICONEXCLAMATION | MB_OK);
+		return 0;
+	}
+
+	// Step 2: Creating the Window
+	hwnd = CreateWindowEx(
+		WS_EX_CLIENTEDGE,
+		g_szClassName,
+		"The title of my window",
+		WS_OVERLAPPEDWINDOW,
+		CW_USEDEFAULT, CW_USEDEFAULT, 640, 480,
+		NULL, NULL, hInstance, NULL);
+
+	if(hwnd == NULL) {
+		MessageBox(NULL, "Window Creation Failed!", "Error!", MB_ICONEXCLAMATION | MB_OK);
+		return 0;
+	}
+
+	ShowWindow(hwnd, nCmdShow);
+	UpdateWindow(hwnd);
+
+	// Step 3: The Message Loop
+	while(GetMessage(&Msg, NULL, 0, 0) > 0) {
+		TranslateMessage(&Msg);
+		DispatchMessage(&Msg);
+	}
+	return Msg.wParam;
+}
\ No newline at end of file