My OnPaint() function calls several other drawing functions.
void CGraph::OnPaint ()
{
CPaintDC dc(this);
// CMemDC DC(&dc);
dc.SetViewportOrg (0, 400);
dc.SetMapMode(MM_ISOTROPIC);
dc.SetWindowExt(1000, 800);
dc.SetViewportExt(1000, -800);
ProcessData ();
DrawCoordinateSystem (&dc);
DrawGrid (&dc);
DrawGraph (&dc);
}
Example of DrawCoordianteSystem:
void CGraph::DrawCoordinateSystem (CDC* pDC)
{
CPen PenBlack (PS_SOLID, 1, RGB(0, 0, 0));
pDC->SelectObject (PenBlack);
// Rectangle round the system
pDC->Rectangle (0, -400, 1000, 400);
// Horizontal axis
pDC->MoveTo (0, 0);
pDC->LineTo (1000, 0);
pDC->SetTextColor (RGB(0,0,0));
pDC->SetBkColor (RGB(240, 240, 240));
pDC->TextOut (1001, 0, L"0");
// Vertical axis
pDC->MoveTo (0, -400);
pDC->LineTo (0, 400);
}
I now want to avoid flickering with CMemDC. However, i can't get it to work right. Can somebody show me how to implement CMemDC right?
Thanks
You need to load the memory DC with a bitmap to then BitBlt to the screen DC.
Try something like:
CDC dcMem;
CBitmap bitmap;
dcMem.CreateCompatibleDC( pDC );
bitmap.CreateCompatibleBitmap(pDC, rect.Width(), rect.Height())
CBitmap* pOldBitmap = dcMem.SelectObject(&bitmap);
... DO ALL YOUR DRAWING TO dcMem ...
pDC->BitBlt(rect.left, rect.top, rect.Width(), rect.Height(), &dcMem, 0, 0, SRCCOPY);
dcMem.SelectObject(pOldBitmap)
To avoid flickers you should draw everything on CMemDC and BitBlt it to the real DC.
Secondly add windows message handler for WM_ERASEBKGND message and change the code to
BOOL CGraph::OnEraseBkgnd(CDC* pDC)
{
return TRUE;
}
Related
I am having some difficulties in correctly populating a CListCtrl with thumbnails of monitor displays.
On the right of my CDialog I have a static control and I render the image on a white canvas like this:
void CCenterCursorOnScreenDlg::OnDrawItem(int nIDCtl, LPDRAWITEMSTRUCT lpDrawItemStruct)
{
if (nIDCtl == IDC_STATIC_MONITOR && !m_imgPreview.IsNull())
{
// Set the mode
SetStretchBltMode(lpDrawItemStruct->hDC, HALFTONE);
// Wipe the canvas
FillRect(lpDrawItemStruct->hDC, &lpDrawItemStruct->rcItem, static_cast<HBRUSH>(GetStockObject(WHITE_BRUSH)));
// Get canvas rectangle
const CRect rectCanvas(lpDrawItemStruct->rcItem);
// Calculate ratio factors
const float nRatioImage = m_imgPreview.GetWidth() / static_cast<float>(m_imgPreview.GetHeight());
const float nRatioCanvas = rectCanvas.Width() / static_cast<float>(rectCanvas.Height());
// Calculate new rectangle size
// Account for portrait images (negative values)
CRect rectDraw = rectCanvas;
if (nRatioImage > nRatioCanvas)
rectDraw.SetRect(0, 0, rectDraw.right, static_cast<int>(rectDraw.right / nRatioImage));
else if (nRatioImage < nRatioCanvas)
rectDraw.SetRect(0, 0, static_cast<int>((rectDraw.bottom * nRatioImage)), rectDraw.bottom);
// Add a margin
rectDraw.DeflateRect(5, 5);
// Move to center
const CSize ptOffset = rectCanvas.CenterPoint() - rectDraw.CenterPoint();
rectDraw.OffsetRect(ptOffset);
// Add a black frame
FrameRect(lpDrawItemStruct->hDC, &lpDrawItemStruct->rcItem, static_cast<HBRUSH>(GetStockObject(BLACK_BRUSH)));
// Draw
m_imgPreview.Draw(lpDrawItemStruct->hDC, rectDraw);
return;
}
CDialogEx::OnDrawItem(nIDCtl, lpDrawItemStruct);
}
The above works beautifully:
But I have problems with the CListCtrl versions of the images. For instance, I am losing the colouring as you can see.
My CImageList is created like this:
m_ImageListThumb.Create(THUMBNAIL_WIDTH, THUMBNAIL_HEIGHT, ILC_COLOR32, 0, 1);
m_ListThumbnail.SetImageList(&m_ImageListThumb, LVSIL_NORMAL);
I then create all the thumbnails by calling DrawThumbnails() in OnInitDialog:
void CCenterCursorOnScreenDlg::DrawThumbnails()
{
int monitorIndex = 0;
m_ListThumbnail.SetRedraw(FALSE);
for (auto& strMonitor : m_monitors.strMonitorNames)
{
CImage img;
CreateMonitorThumbnail(monitorIndex, img, true);
CBitmap* pImage = new CBitmap();
pImage->Attach((HBITMAP)img);
m_ImageListThumb.Add(pImage, nullptr);
CString strMonitorDesc = m_monitors.strMonitorNames.at(monitorIndex);
strMonitorDesc.AppendFormat(L" (Screen %d)", monitorIndex + 1);
m_ListThumbnail.InsertItem(monitorIndex, strMonitorDesc, monitorIndex);
monitorIndex++;
delete pImage;
}
m_ListThumbnail.SetRedraw(TRUE);
}
The CreateMonitorThumbnail function:
BOOL CCenterCursorOnScreenDlg::CreateMonitorThumbnail(const int iMonitorIndex, CImage &rImage, bool bSmall)
{
const CRect rcCapture = m_monitors.rcMonitors.at(iMonitorIndex);
// destroy the currently contained bitmap to create a new one
rImage.Destroy();
auto nWidth = rcCapture.Width();
auto nHeight = rcCapture.Height();
if (bSmall)
{
nWidth = THUMBNAIL_WIDTH;
nHeight = THUMBNAIL_HEIGHT;
}
// create bitmap and attach it to this object
if (!rImage.Create(nWidth, nHeight, 32, 0))
{
AfxMessageBox(L"Cannot create image!", MB_ICONERROR);
return FALSE;
}
// create virtual screen DC
CDC dcScreen;
dcScreen.CreateDC(_T("DISPLAY"), nullptr, nullptr, nullptr);
// copy the contents from the virtual screen DC
BOOL bRet = FALSE;
if (bSmall)
{
CRect rt(0, 0, nWidth, nHeight);
//::FillRect(rImage.GetDC(), rt, static_cast<HBRUSH>(GetStockObject(WHITE_BRUSH)));
bRet = ::StretchBlt(rImage.GetDC(), 0, 0,
nWidth,
nHeight,
dcScreen.m_hDC,
rcCapture.left,
rcCapture.top,
rcCapture.Width(),
rcCapture.Height(), SRCCOPY | CAPTUREBLT);
}
else
{
bRet = ::BitBlt(rImage.GetDC(), 0, 0,
rcCapture.Width(),
rcCapture.Height(),
dcScreen.m_hDC,
rcCapture.left,
rcCapture.top, SRCCOPY | CAPTUREBLT);
}
// do cleanup and return
dcScreen.DeleteDC();
rImage.ReleaseDC();
return bRet;
}
Ideally I want to have exactly the same kind of visual image as on the right, but obviously resized down. How do I fix this?
I simplified the converting from CImage to CBitmap but it made no difference:
void CCenterCursorOnScreenDlg::DrawThumbnails()
{
int monitorIndex = 0;
// Stop redrawing the CListCtrl
m_ListThumbnail.SetRedraw(FALSE);
// Loop monitor info
for (auto& strMonitor : m_monitors.strMonitorNames)
{
// Create the thumbnail image
CImage monitorThumbnail;
CreateMonitorThumbnail(monitorIndex, monitorThumbnail, true);
// Convert it to a CBitmap
CBitmap* pMonitorThumbnailBitmap = CBitmap::FromHandle(monitorThumbnail);
// Add the CBitmap to the CImageList
m_ImageListThumb.Add(pMonitorThumbnailBitmap, nullptr);
// Build the caption description
CString strMonitorDesc = m_monitors.strMonitorNames.at(monitorIndex);
strMonitorDesc.AppendFormat(L" (Screen %d)", monitorIndex + 1);
// Add the item to the CListCtrl
m_ListThumbnail.InsertItem(monitorIndex, strMonitorDesc, monitorIndex);
monitorIndex++;
}
// Start redrawiung the CListCtrl again
m_ListThumbnail.SetRedraw(TRUE);
}
If I change my code to pass false for the last parameter, so that it uses the original captured images without scaling down:
The colours are god there, so it is when I do:
if (bSmall)
{
CRect rt(0, 0, nWidth, nHeight);
//::FillRect(rImage.GetDC(), rt, static_cast<HBRUSH>(GetStockObject(WHITE_BRUSH)));
bRet = ::StretchBlt(rImage.GetDC(), 0, 0,
nWidth,
nHeight,
dcScreen.m_hDC,
rcCapture.left,
rcCapture.top,
rcCapture.Width(),
rcCapture.Height(), SRCCOPY | CAPTUREBLT);
}
that it messes up.
My issue was did not have anything to do with OnDrawItem. I simply included that to indicate how the image on the right was being rendered. I thought it may helped as background information. But it has probably confused the question and I may take it out in the long run!
Based on the comments I was reminded about SetStretchBltMode which was missing from CreateMonitorThumbnail. So, I now have this function:
BOOL CCenterCursorOnScreenDlg::CreateMonitorThumbnail(const int iMonitorIndex, CImage &rImage, bool bResizeAsThumbnail)
{
const CRect rcCapture = m_monitors.rcMonitors.at(iMonitorIndex);
// Destroy the currently contained bitmap to create a new one
rImage.Destroy();
// Massage the dimensions as we want a thumbnail
auto nWidth = rcCapture.Width();
auto nHeight = rcCapture.Height();
if (bResizeAsThumbnail)
{
nWidth = m_iThumbnailWidth;
auto dRatio = rcCapture.Width() / nWidth;
//nHeight = m_iThumbnailHeight;
nHeight = static_cast<int>(rcCapture.Height() / dRatio);
if (nHeight > m_iThumbnailHeight)
{
AfxMessageBox(L"Need to investigate!");
}
}
// Create bitmap and attach it to this object
if (!rImage.Create(nWidth, nHeight, 32, 0))
{
AfxMessageBox(L"Cannot create image!", MB_ICONERROR);
return FALSE;
}
// Create virtual screen DC
CDC dcScreen;
dcScreen.CreateDC(L"DISPLAY", nullptr, nullptr, nullptr);
// Copy (or resize) the contents from the virtual screen DC
BOOL bRet = FALSE;
auto dcImage = rImage.GetDC();
if (bResizeAsThumbnail)
{
// Set the mode first!
SetStretchBltMode(dcImage, COLORONCOLOR);
CPen penBlack;
penBlack.CreatePen(PS_SOLID, 3, RGB(0, 0, 0));
::Rectangle(dcImage, 0, 0, m_iThumbnailWidth, m_iThumbnailHeight);
int iTop = (m_iThumbnailHeight - nHeight) / 2;
// Copy (and resize)
bRet = ::StretchBlt(dcImage, 0, iTop,
nWidth,
nHeight,
dcScreen.m_hDC,
rcCapture.left,
rcCapture.top,
rcCapture.Width(),
rcCapture.Height(), SRCCOPY | CAPTUREBLT);
}
else
{
// Copy
bRet = ::BitBlt(dcImage, 0, 0,
rcCapture.Width(),
rcCapture.Height(),
dcScreen.m_hDC,
rcCapture.left,
rcCapture.top, SRCCOPY | CAPTUREBLT);
}
// Do cleanup and return
dcScreen.DeleteDC();
rImage.ReleaseDC();
return bRet;
}
That was the key to getting the thumbnail showing with the right colours:
I need to print some text (using font specified), than print a bitmap, using MFC. I can draw text on bitmap, than print this bitmap, using code below - but I need to print text, and than print bitmap in the bottom. The bitmap must be loaded from file.
CFont j1;
j1.CreateFont(
120, // nHeight
120, // nWidth
0, // nEscapement
0, // nOrientation
FW_NORMAL, // nWeight
FALSE, // bItalic
FALSE, // bUnderline
0, // cStrikeOut
RUSSIAN_CHARSET, // nCharSet
OUT_DEFAULT_PRECIS, // nOutPrecision
CLIP_DEFAULT_PRECIS, // nClipPrecision
DEFAULT_QUALITY, // nQuality
DEFAULT_PITCH | FF_SWISS, // nPitchAndFamily
"Arial"); // lpszFacename // lpszFacename
int w = 600, h = 400;
CClientDC dc(this);
CBitmap bmp;
CDC memdc;
memdc.CreateCompatibleDC(&dc);
bmp.CreateCompatibleBitmap(&dc, w, h);
if (!bmp.Attach(::LoadImage(
::GetModuleHandle(NULL), "D:\\UPM\\BMP\\Login.bmp", IMAGE_BITMAP, 0, 0,
LR_LOADFROMFILE | LR_CREATEDIBSECTION | LR_DEFAULTSIZE))) {
AfxMessageBox(_T("Error loading bitmap!")); return;
}
BITMAP bm;
bmp.GetBitmap(&bm);
auto oldbmp = memdc.SelectObject(bmp);
CFont* pOldFont = memdc.SelectObject(&j1);
//draw on bitmap
///memdc.FillSolidRect(0, 0, w, h, RGB(200, 200, 200));
memdc.SetTextColor(RGB(255, 0, 0));
CRect rc(0, 0, w, h);
memdc.DrawText("qwerty\nrtrtrt\nttttt", &rc, DT_WORDBREAK | DT_EXPANDTABS | DT_CENTER);
///pDC->DrawText(dpu, strRect, DT_WORDBREAK | DT_EXPANDTABS | DT_CENTER);
//dc.BitBlt(0, 0, w, h, &memdc, 0, 0, SRCCOPY);//optional: draw the bitmap on dialog
CPrintDialog pd(false);
if (pd.DoModal() == IDOK)
{
CDC PrintDC;
HDC hdc = pd.GetPrinterDC();
PrintDC.Attach(hdc);
DOCINFO docinfo = { sizeof(docinfo) };
docinfo.lpszDocName = "Print test";
PrintDC.StartDoc(&docinfo);
PrintDC.StartPage();
PrintDC.BitBlt(0, 0, w, h, &memdc, 0, 0, SRCCOPY);
PrintDC.EndPage();
PrintDC.EndDoc();
}
dc.SelectObject(oldbmp);
CClientDC dc(this);
dc.DrawText(...);
...
PrintDC.BitBlt(0, 0, w, h, &memdc, 0, 0, SRCCOPY);
You are drawing text on display's "client DC", then drawing a bitmap on a "printer DC".
Use instead a paint function for everything, and a paint_bitmap function to make things easier.
void paint_bitmap(CDC& dc, CBitmap &bmp, CRect rc)
{
CDC memdc;
memdc.CreateCompatibleDC(&dc);
auto oldbmp = memdc.SelectObject(&bmp);
dc.BitBlt(rc.left, rc.top, rc.Width(), rc.Height(), &memdc, 0, 0, SRCCOPY);
memdc.SelectObject(oldbmp);
}
void paint(CDC& dc)
{
CBitmap bmp;
if (!bmp.Attach(...))...
dc.DrawText(L"text", &rc, ...);
rc.OffsetRect(0, 200);
paint_bitmap(dc, bmp, rc);
}
...
CPrintDialog pd(false);
if (pd.DoModal() == IDOK)
{
HDC hdc = pd.GetPrinterDC();
if (hdc)
{
...
dc.StartPage();
paint(dc); //<- use this for printer or display
dc.EndPage();
}
To print directly to default printer:
CPrintDialog pd(false);
if (pd.GetDefaults() && pd.m_pd.hDC)
{
CDC dc;
dc.Attach(pd.m_pd.hDC);
DOCINFO docinfo = { sizeof(docinfo) };
docinfo.lpszDocName = L"Print test";
dc.StartDoc(&docinfo);
dc.StartPage();
paint(dc);
dc.EndPage();
dc.EndDoc();
}
else
{
MessageBox(L"no default printer...");
}
or if you want a particular printer which you are sure is there, use
HDC hdc = CreateDC(L"WINSPOOL", L"Microsoft Print to PDF", NULL, NULL);
if (hdc)
{
CDC dc;
dc.Attach(hdc);
...
//DeleteDC(hdc); CDC will take care of delete
}
I want to print a bitmap. To avoid printing small bitmap I set CScrollView mode as MM_LOMETRIC with sizes 3830 x 1995. I have created the bitmap and made the bitblt to the screen. There were everythig just like I want on the screen and on the print preview but when I printed the document I've got very bad result.
The same picture on print preview.
It seems to me that printer does not see a bitmap the same way as print preview does.
Pay attantion that the first ractangle puts directly on the DC and memDC puts into it.
Are there any ideas how to fix this mismatch between print previw and the real printing?
Project files
void OnDraw()
{
CPen pen;
pen.CreatePen(PS_SOLID, 1, RGB(0, 0, 0));
CPen* OldPen = pDC->SelectObject(&pen);
CRect rcView;
GetClientRect(rcView);
int iClientWidth = rcView.right;
int iClientHeight = rcView.bottom;
int iMemWidth = 1900;
int iMemHeight = 950;
CDC memDC;
CBitmap memBitmap;
memDC.CreateCompatibleDC(pDC);
memBitmap.CreateCompatibleBitmap(pDC, iMemWidth, iMemHeight);
memDC.SelectObject(&memBitmap);
memDC.SetMapMode(MM_LOMETRIC);
CPen pen1;
pen1.CreatePen(PS_SOLID, 3, RGB(0, 0, 0));
memDC.SelectObject(&pen1);
CBrush brBK;
brBK.CreateSolidBrush(RGB(255, 255, 255));
memDC.SelectObject(&brBK);
RECT rc;
rc.left = 0;
rc.top = 0;
rc.right = iMemWidth;
rc.bottom = iMemHeight;
memDC.FillRect(&rc, &brBK);
memDC.Rectangle(rc.left, rc.top, rc.right, -rc.bottom);
memDC.MoveTo(0, 0);
memDC.LineTo(1900, -950);
memDC.MoveTo(0, -950);
memDC.LineTo(200, -750);
CFont font;
font.CreateFont(
50, // nHeight
0, // nWidth
0, // nEscapement
0, // nOrientation
FW_NORMAL, // nWeight
FALSE, // bItalic
FALSE, // bUnderline
0, // cStrikeOut
ANSI_CHARSET, // nCharSet
OUT_DEFAULT_PRECIS, // nOutPrecision
CLIP_DEFAULT_PRECIS, // nClipPrecision
DEFAULT_QUALITY, // nQuality
DEFAULT_PITCH | FF_SWISS, // nPitchAndFamily
_T("Arial"));
memDC.SelectObject(&font);
memDC.TextOut(100, -100, _T("Hello"));
pDC->BitBlt(10, -10, iMemWidth, -iMemHeight, &memDC, 0, 0, SRCCOPY);
font.DeleteObject();
brBK.DeleteObject();
memDC.DeleteDC();
memBitmap.DeleteObject();
pen.DeleteObject();
pen1.DeleteObject();
}
void OnInitialUpdate()
{
CScrollView::OnInitialUpdate();
CSize sizeTotal;
sizeTotal.cx = 3830;
sizeTotal.cy = 1995;
SetScrollSizes(MM_LOMETRIC, sizeTotal);
}
I am new to processing, currently I want to display a 3D ball and also add a text label to the 3D ball.
I am using the code as below:
// this function is called when this sketch is first loaded
void setup()
{
// choose size (width, height) of your sketch
size(720, 546, P3D);
// Choose background color for your sketch
background(0);
}
// This function is called repeatedly to draw stuff on screen.
void draw()
{
lights();
pushMatrix();
translate(500, height*0.35, 0);
fill(236,112,20);
noStroke();
sphere(40);
popMatrix();
//fill(255);
fill(255,112,20);
textAlign(CENTER);
textSize(15);
stroke(10);
text("hihihihi", 500, height*0.35);
}
It turned out that the text "hihihihi" is covered by the ball, but when I do it with 2D object it displays good. Is there anything wrong here, can anyone tell me what might be the problem of my code?Thanks!
Notice that your sphere has a radius of 40 which is means a diameter of 80 and you're drawing both the text and sphere at the same horizontal position(500).
Move the text to the right to avoid the sphere occluding it:
void setup()
{
size(720, 546, P3D);
background(0);
}
void draw()
{
lights();
pushMatrix();
translate(500, height*0.35, 0);
fill(236, 112, 20);
noStroke();
sphere(40);
popMatrix();
fill(255, 112, 20);
textAlign(CENTER);
textSize(15);
stroke(10);
text("hihihihi", 585, height*0.35);//make sure the text isn't occluded by anything else(like a sphere)
}
If you want to render text on a sphere I recommend trying PShape and PGraphics.
Here's a minimal example:
PShape sphere;
void setup()
{
size(720, 546, P3D);
background(0);
PGraphics sphereTexture = createGraphics(40,40);
sphereTexture.beginDraw();
sphereTexture.background(236, 112, 20);
sphereTexture.fill(255);
sphereTexture.text("Hi",20,20);
sphereTexture.endDraw();
sphere = createShape(SPHERE, 40);
sphere.disableStyle();
noStroke();
sphere.setTexture(sphereTexture);
}
void draw()
{
lights();
pushMatrix();
translate(500, height*0.35, 0);
fill(236, 112, 20);
noStroke();
shape(sphere,0,0);
popMatrix();
fill(255, 112, 20);
textAlign(CENTER);
textSize(15);
stroke(10);
text("hihihihi", 585, height*0.35);//make sure the text isn't occluded by anything else(like a sphere)
}
I'm having an SVG with 2 layers (back, front).
I need to fill the back with a color (the color will be random).
But the front must stay as it is.
How can I fill the back without affecting the front?
PShape elem;
PShape back;
PShape front;
void setup()
{
size(900,600);
background(255);
fill(100);
elem = loadShape("resources/images/elem.svg");
back = elem.getChild("back");
front = elem.getChild("front");
smooth();
noLoop();
}
void draw(){
elem.disableStyle();
fill(0, 51, 102);
noStroke();
shape(back, 50, 50, 250, 250);
shape(front, 50, 50, 250, 250);
}
Thank you for your help.
Hard to test for your exact setup without the svg.
Still, you should be able to isolate drawing styles for parts of your shapes using pushStyle(),popStyle() pairs.
e.g.
PShape elem;
PShape back;
PShape front;
void setup()
{
size(900,600);
background(255);
fill(100);
elem = loadShape("resources/images/elem.svg");
back = elem.getChild("back");
front = elem.getChild("front");
smooth();
noLoop();
}
void draw(){
elem.disableStyle();
pushStyle();
fill(0, 51, 102);
noStroke();
shape(back, 50, 50, 250, 250);
popStyle();
pushStyle();
shape(front, 50, 50, 250, 250);
popStyle();
}
Indenting is just a visual cue, not actually needed.