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Direct3D Issue

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I'm starting to get into the 3D scheme, I've built a software rendering engine, and am currently getting into hardware acceleration starting with Direct3D and probably moving to OpenGL. However, I have gotten Direct3D up and running using proper enumeration and such, yet I am having some coordinate system issues. I read some of the SDK Documentation and it told me that Direct3D was based on a left handed coordinate system (positive z-axis going into the screen I believe) along with a countclockwise culling system. All is good until I built a program to render a simple triangle, I pointed the camera down the positive z-axis and translated the triangle forward down the positive z-axis so it could seen. All is fine since it was drawn properly. However, the odd thing is that when I tried moving some of the points, it moved in the opposite direction along the x-axis. for instance, if i thought i was moving it 5 to the right, it would move 5 to the left. I thought for a quick second and knew that for this to happen it would mean my camera is pointing in the wrong direction and for that reason the x-axis has been switched. So I pointed the camera down the negative x-axis along with the translation and it worked fine, everything was moving correctly. So.... do I have my coordinate systems messed up and what I thought was a left handed system is really a right handed system? or is there something in Direct3D that tweaks the direction? Disregard the culling stuff, obviously I had to switch two vertices when I pointed the camera in the other direction. Also note that the up vector on the camera points in the positive y direction. This could also cause this effect since if Direct3D uses a positive y axis that points down, it could also cause the camera to flip the x-axis. However, I think DirectX has a y-axis that points up. - Tom Edited by - olp-fan on 8/27/00 3:08:59 AM Edited by - olp-fan on 8/27/00 3:11:57 AM

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