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/*
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!
$Id$
*/
#include <windows.h>
#include <gd.h>
#include <gdfontg.h>
#include <gdfontl.h>
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 gdImageDetachBuffer(gdImagePtr im)
{
free(im->tpixels);
free(im);
}
BITMAPINFO gdCreateBmp(int width, int height)
{
BITMAPINFO bmp_info;
// 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;
return bmp_info;
}
LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;
int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
PSTR szCmdLine, int iCmdShow)
{
static TCHAR szAppName[] = TEXT ("Bezier") ;
HWND hwnd ;
MSG msg ;
WNDCLASS wndclass ;
wndclass.style = CS_HREDRAW | CS_VREDRAW ;
wndclass.lpfnWndProc = WndProc ;
wndclass.cbClsExtra = 0 ;
wndclass.cbWndExtra = 0 ;
wndclass.hInstance = hInstance ;
wndclass.hIcon = LoadIcon (NULL, IDI_APPLICATION) ;
wndclass.hCursor = LoadCursor (NULL, IDC_ARROW) ;
wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;
wndclass.lpszMenuName = NULL ;
wndclass.lpszClassName = szAppName ;
if (!RegisterClass (&wndclass)) {
// UNICODE-Compilierung ist die einzige realistische Fehlermöglichkeit
MessageBox (NULL, TEXT ("Programm arbeitet mit Unicode und setzt Windows NT voraus!"),
szAppName, MB_ICONERROR) ;
return 0 ;
}
hwnd = CreateWindow (szAppName, TEXT ("Bezierkurven"),
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT, CW_USEDEFAULT,
CW_USEDEFAULT, CW_USEDEFAULT,
NULL, NULL, hInstance, NULL) ;
ShowWindow (hwnd, iCmdShow) ;
UpdateWindow (hwnd) ;
while (GetMessage (&msg, NULL, 0, 0)) {
TranslateMessage (&msg) ;
DispatchMessage (&msg) ;
}
return msg.wParam ;
}
void DrawBezier (HDC hdc, POINT apt[])
{
PolyBezier (hdc, apt, 4) ;
MoveToEx (hdc, apt[0].x, apt[0].y, NULL) ;
LineTo (hdc, apt[1].x, apt[1].y) ;
MoveToEx (hdc, apt[2].x, apt[2].y, NULL) ;
LineTo (hdc, apt[3].x, apt[3].y) ;
}
void gdDrawImage(HDC hdc, RECT *rc)
{
HDC mem_dc;
BITMAPINFO bmp_info;
void* bits;
HBITMAP bmp, temp;
gdImagePtr im;
int width, height, stride;
int white, black, blue, red;
char *s = "Hello world!";
gdFontPtr lfont, gfont;
width = rc->right - rc->left;
height = rc->bottom - rc->top;
bmp_info = gdCreateBmp(width, height);
// Create memory device context
mem_dc = CreateCompatibleDC(hdc);
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);
/*stride = ((width * 1 + 3) >> 2) << 2;*/
// always uses 32bit in BMPINFO
stride = width;
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;
}
// Start of GD drawing
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(hdc, rc->left, rc->top, width, height, mem_dc, 0, 0, SRCCOPY);
// Free
gdImageDetachBuffer(im);
SelectObject(mem_dc, temp);
DeleteObject(bmp);
DeleteObject(mem_dc);
}
LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
static POINT apt[4] ;
HDC hdc ;
int cxClient, cyClient ;
PAINTSTRUCT ps ;
RECT rc;
GetClientRect(hwnd, &rc);
switch (message) {
case WM_SIZE:
cxClient = LOWORD (lParam) ;
cyClient = HIWORD (lParam) ;
apt[0].x = cxClient / 4 ;
apt[0].y = cyClient / 2 ;
apt[1].x = cxClient / 2 ;
apt[1].y = cyClient / 4 ;
apt[2].x = cxClient / 2 ;
apt[2].y = 3 * cyClient / 4 ;
apt[3].x = 3 * cxClient / 4 ;
apt[3].y = cyClient / 2 ;
return 0 ;
case WM_LBUTTONDOWN:
case WM_RBUTTONDOWN:
case WM_MOUSEMOVE:
if (wParam & MK_LBUTTON || wParam & MK_RBUTTON) {
hdc = GetDC (hwnd) ;
// alte Kurve löschen (mit Weiß übermalen)
SelectObject (hdc, GetStockObject (WHITE_PEN)) ;
DrawBezier (hdc, apt) ;
if (wParam & MK_LBUTTON) {
apt[1].x = LOWORD (lParam) ;
apt[1].y = HIWORD (lParam) ;
}
if (wParam & MK_RBUTTON) {
apt[2].x = LOWORD (lParam) ;
apt[2].y = HIWORD (lParam) ;
}
// neue Kurve (mit Schwarz) zeichnen
SelectObject (hdc, GetStockObject (BLACK_PEN)) ;
gdDrawImage(hdc, &rc);
DrawBezier (hdc, apt) ;
ReleaseDC (hwnd, hdc) ;
}
return 0 ;
case WM_PAINT:
hdc = BeginPaint (hwnd, &ps) ;
GetClientRect(hwnd, &rc);
gdDrawImage(hdc, &rc);
DrawBezier (hdc, apt) ;
EndPaint (hwnd, &ps) ;
return 0 ;
case WM_DESTROY:
PostQuitMessage (0) ;
return 0 ;
}
return DefWindowProc (hwnd, message, wParam, lParam) ;
}
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