I need to draw something in DirectX 9.
I am interested to work in a way that the coordinates will be adjusted to pixels, while (0,0) will be the TopLeft corner. Here is what I do:
RECT clientRect;
::GetClientRect(m_hWIN, &clientRect);
D3DXMATRIX matOrtho2D, matIdentity;
D3DXMatrixOrthoOffCenterLH(&matOrtho2D, 0, clientRect.right, 0, clientRect.bottom, 0.0f, 1.0f);
D3DXMatrixIdentity(&matIdentity);
g_pDirect3D_Device->SetTransform(D3DTS_PROJECTION, &matOrtho2D);
g_pDirect3D_Device->SetTransform(D3DTS_WORLD, &matIdentity);
g_pDirect3D_Device->SetTransform(D3DTS_VIEW, &matIdentity);
This works fine, except the (0,0) is the BottomLeft corner. How can I change it?
Thanks!
This should be add to code:
D3DXMATRIX matTranslate, matFlip;
D3DXMatrixTranslation(&matTranslate, 0, clientRect.bottom, 0.0f);
D3DXMatrixRotationX(&matFlip, D3DXToRadian(180));
D3DXMATRIX matCoordTransform = matFlip * matTranslate;
g_pDirect3D_Device->SetTransform(D3DTS_WORLD, &matCoordTransform);
Related
I followed a guide to draw a Lorenz system in 2D.
I want now to extend my project and switch from 2D to 3D. As far as I know I have to substitute the gluOrtho2D call with either gluPerspective or glFrustum. Unfortunately whatever I try is useless.
This is my initialization code:
// set the background color
glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
/// set the foreground (pen) color
glColor4f(1.0f, 1.0f, 1.0f, 1.0f);*/
// set the foreground (pen) color
glColor4f(1.0f, 1.0f, 1.0f, 0.02f);
// enable blending
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
// enable point smoothing
glEnable(GL_POINT_SMOOTH);
glPointSize(1.0f);
// set up the viewport
glViewport(0, 0, 400, 400);
// set up the projection matrix (the camera)
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
//gluOrtho2D(-2.0f, 2.0f, -2.0f, 2.0f);
gluPerspective(45.0f, 1.0f, 0.1f, 100.0f); //Sets the frustum to perspective mode
// set up the modelview matrix (the objects)
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
while to draw I do this:
glClear(GL_COLOR_BUFFER_BIT);
// draw some points
glBegin(GL_POINTS);
// go through the equations many times, drawing a point for each iteration
for (int i = 0; i < iterations; i++) {
// compute a new point using the strange attractor equations
float xnew=z*sin(a*x)+cos(b*y);
float ynew=x*sin(c*y)+cos(d*z);
float znew=y*sin(e*z)+cos(f*x);
// save the new point
x = xnew;
y = ynew;
z = znew;
// draw the new point
glVertex3f(x, y, z);
}
glEnd();
// swap the buffers
glutSwapBuffers();
the problem is that I don't visualize anything in my window. It's all black. What am I doing wrong?
The name "gluOrtho2D" is a bit misleading. In fact gluOrtho2D is probably the most useless function ever. The definition of gluOrtho2D is
void gluOrtho2D(
GLdouble left,
GLdouble right,
GLdouble bottom,
GLdouble top )
{
glOrtho(left, right, bottom, top, -1, 1);
}
i.e. the only thing it does it calling glOrtho with default values for near and far. Wow, how complicated and ingenious </sarcasm>.
Anyway, even if it's called ...2D, there's nothing 2-dimensional about it. The projection volume still has a depth range of [-1 ; 1] which is perfectly 3-dimensional.
Most likely the points generated lie outside the projection volume, which has a Z value range of [0.1 ; 100] in your case, but your points are confined to the range [-1 ; 1] in either axis (and IIRC the Z range of the strange attractor is entirely positive). So you have to apply some translation to see something. I suggest you choose
near = 1
far = 10
and apply a translation of Z: -5.5 to move things into the center of the viewing volume.
I'm new to directx and finally I managed to load an image which I want to display as background image/texture
Defining image
void setBGImage(std::string path)
{
D3DXCreateTextureFromFileA(m_Device, path.c_str(), &m_BGImage);
m_BGImageCenter = D3DXVECTOR3(450.0f, 250.0f, 0.0f); // Image is 900x500
}
Drawing image
void DrawBackground()
{
m_Sprite->Begin(D3DXSPRITE_OBJECTSPACE|D3DXSPRITE_DONOTMODIFY_RENDERSTATE);
// Texture tiling
/*
D3DXMATRIX texScaling;
D3DXMatrixScaling(&texScaling, 1.0f, 1.0f, 0.0f);
m_Device->SetTransform(D3DTS_TEXTURE0, &texScaling);*/
//D3DXMATRIX T, S, R;
//D3DXMatrixTranslation(&T, 0.0f, 0.0f, 0.0f);
//D3DXMatrixScaling(&S, 1.0f, 1.0f, 0.0f);
//D3DXMatrixRotationZ(&R, 0.45f);
//m_Sprite->SetTransform(&(S*T));
m_Sprite->Draw(m_BGImage, 0, &m_BGImageCenter, 0, D3DCOLOR_XRGB(255, 255, 255));
m_Sprite->Flush();
m_Sprite->End();
}
onResetDevice (is getting called at startup)
void onResetDevice()
{
m_Sprite->OnResetDevice();
// Sets up the camera 640 units back looking at the origin.
D3DXMATRIX V;
D3DXVECTOR3 pos(0.0f, 0.0f, -640.0f); // This distance is just a test value to get only the image and no white background/border as soon as I have it centered I will adjust it.
D3DXVECTOR3 up(0.0f, 1.0f, 0.0f);
D3DXVECTOR3 target(0.0f, 0.0f, 0.0f);
D3DXMatrixLookAtLH(&V, &pos, &target, &up);
m_Device->SetTransform(D3DTS_VIEW, &V);
// The following code defines the volume of space the camera sees.
D3DXMATRIX P;
RECT R;
GetClientRect(m_hWnd, &R);
float width = (float)R.right;
float height = (float)R.bottom;
D3DXMatrixPerspectiveFovLH(&P, D3DX_PI*0.25f, width/height, 0.0f, 1.0f);
m_Device->SetTransform(D3DTS_PROJECTION, &P);
// This code sets texture filters, which helps to smooth out disortions when you scale a texture.
m_Device->SetSamplerState(0, D3DSAMP_MAGFILTER, D3DTEXF_LINEAR);
m_Device->SetSamplerState(0, D3DSAMP_MINFILTER, D3DTEXF_LINEAR);
m_Device->SetSamplerState(0, D3DSAMP_MIPFILTER, D3DTEXF_LINEAR);
// This line of code disables Direct3D lighting.
m_Device->SetRenderState(D3DRS_LIGHTING, false);
// The following code specifies an alpha test and reference value.
m_Device->SetRenderState(D3DRS_ALPHAREF, 10);
m_Device->SetRenderState(D3DRS_ALPHAFUNC, D3DCMP_GREATER);
// The following code is used to setup alpha blending.
m_Device->SetTextureStageState(0, D3DTSS_ALPHAARG1, D3DTA_TEXTURE);
m_Device->SetTextureStageState(0, D3DTSS_ALPHAOP, D3DTOP_SELECTARG1);
m_Device->SetRenderState(D3DRS_SRCBLEND, D3DBLEND_SRCALPHA);
m_Device->SetRenderState(D3DRS_DESTBLEND, D3DBLEND_INVSRCALPHA);
// Indicates that we are using 2D texture coordinates.
m_Device->SetTextureStageState(0, D3DTSS_TEXTURETRANSFORMFLAGS, D3DTTFF_COUNT2);
}
When I use these methods to render my background image it get's displayed upside down, not centered (little bit to the right) and I've got the feeling the height width ratio isn't correct (image is kinda blurry and it feels like the image is not as high as it's supposed to be).
What did I try?
I tried to adjust various coordinates in order to look at the image from the other side and then rotate it but whatever I tried it turned into a white/non-existing background.
Centering the image is not such a big deal I can just move the camera position but I'm confused since the m_BGImageCenter was supposed to do that for me in the Draw method and it seems to not work 100% correct.
My Questions (I guess it's ok to ask multiple questions in this context):
How can I get the image not upside down (I know how you would do it in theory but I somehow don't get it right, so please give me the coordinates).
Why is the image not centered?
Is it possible that D3DXMatrixPerspectiveFovLH is wrapping my image since it looks a little bit blurry.
I am trying to create a rectangle and colour the inverse (area outside that rectangle) area.
Gdiplus::Region *cropRegion = new Gdiplus::Region(cropRectF);
Gdiplus::Rect gdiCropRect(0.0f, 0.0f, 1000.0f, 1000.0f);
Gdiplus::Rect imageContainer(0.0f, 0.0f, 1000.0f, 1000.0f);
Gdiplus::Region *completeRegion = new Gdiplus::Region(imageContainer);
completeRegion->Intersect(cropRegion);
gdiGraphics.SetClip(completeRegion, Gdiplus::CombineModeXor);
Gdiplus::GraphicsPath *cropRectPath = new Gdiplus::GraphicsPath();
cropRectPath->AddRectangle(cropRectF);
Gdiplus::Pen* myPen = new Gdiplus::Pen(Gdiplus::Color::White);
myPen->SetWidth(1);
gdiGraphics.DrawPath(myPen, cropRectPath);
Gdiplus::SolidBrush dimmingBrush(Gdiplus::Color::MakeARGB(50, 0, 0, 0));
gdiGraphics.FillRegion(&dimmingBrush, completeRegion);
The code till here works perfectly fine,
However when I try to move this rectangle using mouse movements in MouseMove CallBack, it moves but it leaves white traces behind.
I tried to call InvalidateRect in the end but then my rectangle doesn't moves at all.
Any Idea how can old rectangle can be cleared.
I am using GDI+ and C++.
Thanks
I'm new to Direct3D and I was on a project taking pictures from a webcam and draw some 3D objects in front of it.
I was able to render webcam images as background using Orthogonal Projection.
//init matrix
D3DXMatrixOrthoLH(&Ortho, frameWidth, frameHeight, 0.0f, 100.0f);
//some code
D3DXVECTOR3 position = D3DXVECTOR3(0.0f, 0.0f, 100.0f);
g_pSprite->Begin(D3DXSPRITE_OBJECTSPACE);
g_pSprite->Draw(g_pTexture,NULL,¢er,&position,0xFFFFFFFF);
g_pSprite->End();
Then I tried to insert a simple triangle in front of it. The Matrices are setup as follow
D3DXMATRIXA16 matWorld;
D3DXMatrixTranslation( &matWorld, 0.0f,0.0f,5.0f );
g_pd3dDevice->SetTransform( D3DTS_WORLD, &matWorld );
D3DXMATRIXA16 matProj;
D3DXMatrixPerspectiveFovLH( &matProj, D3DX_PI / 4, 1.0f, 1.0f, 100.0f );
g_pd3dDevice->SetTransform( D3DTS_PROJECTION, &matProj );
5.0 should be < 100.0 and the triangle is supposed to be appear in front of the images. However it does not appear unless set the z position to 0. At position 0, i can see the triangle but background is blank.
Do you guys have any suggestions?
I would not draw the webcam image in the object space (D3DXSPRITE_OBJECTSPACE) if you intend to use your image solely for background purpose; something like
D3DXVECTOR3 backPos (0.f, 0.f, 0.f);
pBackgroundSprite->Begin(D3DXSPRITE_ALPHABLEND);
pBackgroundSprite->Draw (pBackgroundTexture,
0,
0,
&backPos,
0xFFFFFFFF);
pBackgroundSprite->End();
should hopefully do what you're looking for.
As a quick fix you could disable depth testing as follows;
g_pd3dDevice->SetRenderState(D3DRS_ZENABLE, D3DZB_FALSE);
This way the z-index of the primitives being drawn should reflect the order in which they are drawn.
Also, try using the PIX debugging tool (this is bundled with the DirectX SDK). This is always my first port of call for drawing discrepancies as it allows you to debug each Draw call separately with access to the depth buffer and transformed vertices.
For some strange reason my depth buffer is not working, i.e. the triangles drawn later always overlap, regardless of their position.
I have these presenter parameters
D3DPRESENT_PARAMETERS d3dpp;
ZeroMemory(&d3dpp, sizeof(d3dpp));
d3dpp.Windowed = TRUE;
d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;
d3dpp.hDeviceWindow = mWindow;
d3dpp.BackBufferFormat = D3DFMT_X8R8G8B8;
d3dpp.BackBufferWidth = mScreenWidth;
d3dpp.BackBufferHeight = mScreenHeight;
d3dpp.EnableAutoDepthStencil = TRUE;
d3dpp.AutoDepthStencilFormat = D3DFMT_D16;
and these render states:
d3dDevice->SetRenderState(D3DRS_LIGHTING, TRUE); // turn off the 3D lighting
d3dDevice->SetRenderState(D3DRS_ZENABLE, TRUE); // turn on the z-buffer
d3dDevice->SetRenderState(D3DRS_NORMALIZENORMALS, TRUE);
d3dDevice->SetRenderState(D3DRS_AMBIENT, D3DCOLOR_XRGB(50, 50, 50)); // ambient light
edit:
thanks for replying. this is the rendering code code:
d3dDevice->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0, 0, 0), 1.0f, 0);
d3dDevice->Clear(0, NULL, D3DCLEAR_ZBUFFER, D3DCOLOR_XRGB(0, 0, 0), 1.0f, 0);
d3dDevice->BeginScene();
// View transform
D3DXMATRIX matView;
D3DXMatrixLookAtLH(&matView,
&PlayerPos, // the camera position
&(LookAtRelative + PlayerPos), // the look-at position
&D3DXVECTOR3 (0.0f, 1.0f, 0.0f)); // the up direction
d3dDevice->SetTransform(D3DTS_VIEW, &matView);
// Projection transform
D3DXMATRIX matProjection;
D3DXMatrixPerspectiveFovLH(&matProjection,
D3DXToRadian(45), // the horizontal field of view
(FLOAT)mScreenWidth / (FLOAT)mScreenHeight, // aspect ratio
0.0f, // the near view-plane
1000.0f); // the far view-plane
d3dDevice->SetTransform(D3DTS_PROJECTION, &matProjection);
for (unsigned int i=0; i < mModels.size(); i++) {
mModels[i]->Draw();
}
d3dDevice->EndScene();
d3dDevice->Present(NULL, NULL, NULL, NULL);
and the Model::Draw() code is this:
void Model :: Draw () {
// Setup the world transform matrix
D3DXMATRIX matScale;
D3DXMATRIX matRotate;
D3DXMATRIX matTranslate;
D3DXMATRIX matWorldTransform;
D3DXMatrixScaling(&matScale, mScale->x, mScale->y, mScale->z);
D3DXMatrixRotationY(&matRotate, 0);
D3DXMatrixTranslation(&matTranslate, mPosition->x, mPosition->y, mPosition->z);
matWorldTransform = matScale * matRotate * matTranslate;
d3dDevice->SetTransform(D3DTS_WORLD, &matWorldTransform);
d3dDevice->SetFVF(CUSTOMFVF);
d3dDevice->SetStreamSource(0, vertexBuffer, 0, sizeof(CUSTOMVERTEX));
d3dDevice->SetIndices(indexBuffer);
d3dDevice->DrawIndexedPrimitive(D3DPT_TRIANGLELIST, 0, 0, vertexCount, 0, indexCount/3);
}
where vertexBuffer and indexBuffer with with their counts are attributes of the class.
Here are some screenshots (FU, spam protection):
1) http://img822.imageshack.us/img822/1705/dx2010080913182262.jpg this is the situation
2) http://img691.imageshack.us/img691/7358/dx2010080913183790.jpg this is the (correct) view when the cube is in front (the cube is drawn later)
3) http://img340.imageshack.us/img340/4720/dx2010080913184509.jpg But when I have the truncated pyramid in front, the cube still overlaps
it's easier to see when you move the camera yourself...
Now that's a gotcha. The problem was me setting the near view plane to 0.0f - when I changed it to something like 0.001f, the z-buffer suddenly started to work.