Sign in to follow this  
chpstcks

OpenGL [edit] choppy panning animation

Recommended Posts

chpstcks    122
hello, I am creating a maximized windowed application (meaning that it plays nice with other windowed application, but occupies the whole screen and does not change the resolution) that pans large textured rectangle (close to 1600x1200) across the screen. My frame rate is decent enough (capped at 35fps), and movement rate is constant. However, the animation is still choppy (it's not unbearable, but just not up to par)... I have the identical app implemented in OpenGL (with frame rate capped at 30) and the animation is far smoother. i logged the application and the biggest difference between the two version is that blt in directx (have to use dx7 for compatibility =/ ) is way slower than SwapBuffers in the opengl version. Whereas swapbuffers takes about 5-15ms per frame, blt/bltfast averages at 25ms. any insights or ideas on why this is the case would be greatly appreciated ^^;; thanks, ~dAviD [Edited by - chpstcks on November 30, 2006 4:02:22 PM]

Share this post


Link to post
Share on other sites
Evil Steve    2017
OpenGL will use hardware for rendering, DirectDraw will almost certainly be software. The equivalent to OpenGL would be Direct3D, not DirectDraw - and you should get performance pretty much identical to OpenGL.

Share this post


Link to post
Share on other sites
chpstcks    122
Quote:
Original post by Evil Steve
OpenGL will use hardware for rendering, DirectDraw will almost certainly be software. The equivalent to OpenGL would be Direct3D, not DirectDraw - and you should get performance pretty much identical to OpenGL.


hmmm... well, I'm using direct3d to draw quads to the offscreen surface, then blt'ing it to the primary; wasn't aware there's another way to do this.... or am i just confused? o_O

Share this post


Link to post
Share on other sites
Evil Steve    2017
Quote:
Original post by chpstcks
Quote:
Original post by Evil Steve
OpenGL will use hardware for rendering, DirectDraw will almost certainly be software. The equivalent to OpenGL would be Direct3D, not DirectDraw - and you should get performance pretty much identical to OpenGL.


hmmm... well, I'm using direct3d to draw quads to the offscreen surface, then blt'ing it to the primary; wasn't aware there's another way to do this.... or am i just confused? o_O
It's been years since I used DDraw - If you're fullscreen, you can flip the surfaces I think. In windowed mode you need to blit the backbuffer to the window, yes.

However, there shouldn't be much of a speed difference between D3D and OpenGL if things are done correctly. I imagine OpenGL has to do something similar to what D3D does behind the scenes too...

Share this post


Link to post
Share on other sites
chpstcks    122
Quote:
Original post by Evil Steve
It's been years since I used DDraw - If you're fullscreen, you can flip the surfaces I think. In windowed mode you need to blit the backbuffer to the window, yes.

However, there shouldn't be much of a speed difference between D3D and OpenGL if things are done correctly. I imagine OpenGL has to do something similar to what D3D does behind the scenes too...


Right, SwapBuffers does functionally the same thing for OpenGL in Windows as Blt does for directX. My blt speed doesn't seems to be dependent on what i'm blt'ing, but what size the primary surface is... i can blt from a 32x32 back surface to a 1200x1600 front surface (or even a blank screen) and it still takes 25ms. I guess this is expected since it's just copying pixels across buffers... i tried messing around with DDBLTFX struct but doesn't seem to matter >_<

is there any reason to believe using IDirect3DDevice8::Present() will be faster than IDirectDrawSurface7::Blt() ?

Share this post


Link to post
Share on other sites
Sc4Freak    643
Yes, because it will render in 3D using 3D Hardware. Let me see if I have this correct: you're using Direct3D to render textured quads to a surface, then using DirectDraw to blit it to the screen? Why not just use Direct3D to render it to the backbuffer?

Share this post


Link to post
Share on other sites
chpstcks    122
Quote:
Original post by Sc4Freak
Yes, because it will render in 3D using 3D Hardware. Let me see if I have this correct: you're using Direct3D to render textured quads to a surface, then using DirectDraw to blit it to the screen? Why not just use Direct3D to render it to the backbuffer?


i do render the rectangle to the back buffer using direct3D, but i still have to blt it to the primary surface since it's a windowed app. So you guys seem to be suggesting that Blt, even with the right flags set, will use software to render rather than hardware? Doesn't that mean all windowed 3D app before Dx8 used software blitting?? o_O?? just seems so strange...

Share this post


Link to post
Share on other sites
chpstcks    122
I played with my app some more and was able to reach a frame rate of ~150fps by giving it exclusive access to the screen... but the panning is STILL not smooth!

So this points to a settings problem rather than a blt problem, but i went through all the render states and texture stage states and i just can't get it to pan smoothly >___<

please help~

i have the following set:

m_pd3dDevice->SetRenderState(D3DRENDERSTATE_AMBIENT, 0xffffffff );
m_pd3dDevice->SetRenderState( D3DRENDERSTATE_ANTIALIAS, D3DANTIALIAS_SORTINDEPENDENT );
m_pd3dDevice->SetRenderState(D3DRENDERSTATE_EDGEANTIALIAS , D3DANTIALIAS_SORTINDEPENDENT );
m_pd3dDevice->SetRenderState( D3DRENDERSTATE_TEXTUREPERSPECTIVE, FALSE );

m_pd3dDevice->SetTextureStageState( 0, D3DTSS_COLORARG1, D3DTA_TEXTURE );
m_pd3dDevice->SetTextureStageState( 0, D3DTSS_COLORARG2, D3DTA_DIFFUSE );
m_pd3dDevice->SetTextureStageState( 0, D3DTSS_COLOROP, D3DTOP_MODULATE );
m_pd3dDevice->SetTextureStageState( 0, D3DTSS_MINFILTER, D3DTFN_LINEAR );
m_pd3dDevice->SetTextureStageState( 0, D3DTSS_MAGFILTER, D3DTFG_LINEAR );
m_pd3dDevice->SetTextureStageState( 0, D3DTSS_ADDRESS, D3DTADDRESS_CLAMP);

//i tried the notearing flag for blt and that didn't help either

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

Sign in to follow this  

  • Similar Content

    • By povilaslt2
      Hello. I'm Programmer who is in search of 2D game project who preferably uses OpenGL and C++. You can see my projects in GitHub. Project genre doesn't matter (except MMO's :D).
    • By ZeldaFan555
      Hello, My name is Matt. I am a programmer. I mostly use Java, but can use C++ and various other languages. I'm looking for someone to partner up with for random projects, preferably using OpenGL, though I'd be open to just about anything. If you're interested you can contact me on Skype or on here, thank you!
      Skype: Mangodoor408
    • By tyhender
      Hello, my name is Mark. I'm hobby programmer. 
      So recently,I thought that it's good idea to find people to create a full 3D engine. I'm looking for people experienced in scripting 3D shaders and implementing physics into engine(game)(we are going to use the React physics engine). 
      And,ye,no money =D I'm just looking for hobbyists that will be proud of their work. If engine(or game) will have financial succes,well,then maybe =D
      Sorry for late replies.
      I mostly give more information when people PM me,but this post is REALLY short,even for me =D
      So here's few more points:
      Engine will use openGL and SDL for graphics. It will use React3D physics library for physics simulation. Engine(most probably,atleast for the first part) won't have graphical fron-end,it will be a framework . I think final engine should be enough to set up an FPS in a couple of minutes. A bit about my self:
      I've been programming for 7 years total. I learned very slowly it as "secondary interesting thing" for like 3 years, but then began to script more seriously.  My primary language is C++,which we are going to use for the engine. Yes,I did 3D graphics with physics simulation before. No, my portfolio isn't very impressive. I'm working on that No,I wasn't employed officially. If anybody need to know more PM me. 
       
    • By Zaphyk
      I am developing my engine using the OpenGL 3.3 compatibility profile. It runs as expected on my NVIDIA card and on my Intel Card however when I tried it on an AMD setup it ran 3 times worse than on the other setups. Could this be a AMD driver thing or is this probably a problem with my OGL code? Could a different code standard create such bad performance?
    • By Kjell Andersson
      I'm trying to get some legacy OpenGL code to run with a shader pipeline,
      The legacy code uses glVertexPointer(), glColorPointer(), glNormalPointer() and glTexCoordPointer() to supply the vertex information.
      I know that it should be using setVertexAttribPointer() etc to clearly define the layout but that is not an option right now since the legacy code can't be modified to that extent.
      I've got a version 330 vertex shader to somewhat work:
      #version 330 uniform mat4 osg_ModelViewProjectionMatrix; uniform mat4 osg_ModelViewMatrix; layout(location = 0) in vec4 Vertex; layout(location = 2) in vec4 Normal; // Velocity layout(location = 3) in vec3 TexCoord; // TODO: is this the right layout location? out VertexData { vec4 color; vec3 velocity; float size; } VertexOut; void main(void) { vec4 p0 = Vertex; vec4 p1 = Vertex + vec4(Normal.x, Normal.y, Normal.z, 0.0f); vec3 velocity = (osg_ModelViewProjectionMatrix * p1 - osg_ModelViewProjectionMatrix * p0).xyz; VertexOut.velocity = velocity; VertexOut.size = TexCoord.y; gl_Position = osg_ModelViewMatrix * Vertex; } What works is the Vertex and Normal information that the legacy C++ OpenGL code seem to provide in layout location 0 and 2. This is fine.
      What I'm not getting to work is the TexCoord information that is supplied by a glTexCoordPointer() call in C++.
      Question:
      What layout location is the old standard pipeline using for glTexCoordPointer()? Or is this undefined?
       
      Side note: I'm trying to get an OpenSceneGraph 3.4.0 particle system to use custom vertex, geometry and fragment shaders for rendering the particles.
  • Popular Now