Making a Surface Transparent
Author
I have a bitmap for crosshairs that I am drawing to the screen using a "LPDIRECT3DSURFACE9" device. I got the backbuffer and loaded the surface with a transparency color. The only problem is when I draw it, no matter what the transparency color is, the part that should be transparent turns up black and blotches out all of the geometry behind it. How can I make it transparent?
Author
Oh. I didn't know you could do that with surfaces. Ok thanks I'll try it.
EDIT:
I just tried it and it doesn't change the results. Here is my code:
EDIT:
I just tried it and it doesn't change the results. Here is my code:
//Draw the HUD g_pD3DDevice->SetRenderState(D3DRS_ALPHATESTENABLE, TRUE); g_pD3DDevice->SetRenderState(D3DRS_ALPHABLENDENABLE, TRUE); g_pD3DDevice->SetRenderState(D3DRS_ALPHAREF, 0x01); //-/Target crossRect.top=height/2-16; crossRect.left=width/2-16; crossRect.bottom=height/2+16; crossRect.right=width/2+16; g_pD3DDevice->GetBackBuffer(0,0,D3DBACKBUFFER_TYPE_MONO, &backbuffer); g_pD3DDevice->StretchRect(cross, NULL, backbuffer, &crossRect, D3DTEXF_NONE); //Done rendering HUD g_pD3DDevice->SetRenderState(D3DRS_ALPHABLENDENABLE, FALSE); g_pD3DDevice->SetRenderState(D3DRS_ALPHATESTENABLE, FALSE);
Sorry big misunderstanding. I thought you use the surface interface to fill a texture and then render a quad as this is the more correct way to render something.
StretchRect should only used in some special cases and not for rendering a HUD.
StretchRect should only used in some special cases and not for rendering a HUD.
Author
Oh. Okay. What should I use then? I was going to use sprites but they didn't seem right because the coordinates were in 3d and it seemed like it would be too hard to calculate a D3DXVECTOR3 for each HUD element. If you are supposed to use a sprite, how do I do it?
Quote:Original post by Programmer101Personally, I'd draw a series of textured quads (Same the D3DXSprite does, really) in screen space. You can do that by using transformed vertices (D3DFVF_XYZRHW if you're using the fixed function pipeline), or by using an orthogonal projection matrix (Which means the viewport will be like a CAD-style window where objects with a greater Z value aren't drawn smaller - See D3DXMatrixOrthoLH)
Oh. Okay. What should I use then? I was going to use sprites but they didn't seem right because the coordinates were in 3d and it seemed like it would be too hard to calculate a D3DXVECTOR3 for each HUD element. If you are supposed to use a sprite, how do I do it?
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