# OpenGL Some transformation Between Direct3D and OPENGL.

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HI,I am referencing a terrain example written by OPENGL.The following is some fragment of code... ...................... glActiveTextureARB(GL_TEXTURE0_ARB); glEnable(GL_TEXTURE_2D); glBindTexture(GL_TEXTURE_2D, m_txt.GetTxtID()); //Activate the second texture ID and bind the fog texture to it glActiveTextureARB(GL_TEXTURE1_ARB); glEnable(GL_TEXTURE_2D); //Here we turn on the COMBINE properties and increase our RGB //gamma for the detail texture. 2 seems to work just right. glTexEnvi(GL_TEXTURE_ENV, GL_RGB_SCALE_ARB, 2); glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_ARB); //Bind the detail texture glBindTexture(GL_TEXTURE_2D, m_cTxtDetail.GetTxtID()); # I know these code set the terrain texture,but I don't know which Direct3d interface could realize the following effect? " glTexEnvi(GL_TEXTURE_ENV, GL_RGB_SCALE_ARB, 2); glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_ARB); " who can tell me? ============================================== The following is about texture coordinate transformation, which is written by OPENGL. //Now we want to enter the texture matrix. This will allow us //to change the tiling of the detail texture. glMatrixMode(GL_TEXTURE); //Reset the current matrix and apply our chosen scale value glLoadIdentity(); glScalef((float)32, (float)32, 32); I rewrote in Direct3D,Is it right?It does not work. // D3DXMATRIX matTexture; D3DXMatrixIdentity( &matTexture ); matTexture._11 = 32.0f; matTexture._22 = 32.0f; matTexture._33 = 32.0f; pD3DDevice->SetTransform( D3DTS_TEXTURE0, &matTexture ); Thanks!

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1) The texel value scaling would by achieved by passing the D3DTOP_MODULATE2X as an argument to SetTextureStageState.

2) There is a convenience function for this, google for D3DXMatrixScaling. Also, you realise you have to actually multiply your transformation matrices with this scaling matrix, and then set it through D3DDevice->SetTransform, right?

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Thank Pauljan!
I just want to expand the texture coordinate,I wrote the following code:

D3DXMATRIX matTexture;
D3DXMatrixIdentity( &matTexture );
D3DXMatrixScaling( &matTexture, 32.0f, 32.0f, 32.0f );
pD3DDevice->SetTransform( D3DTS_TEXTURE0, &matTexture );

But it still doesn't work.Should I pay attention to the calling position of these function? I Call these function, then DrawPrimitiveUp( ).Is there any problem?

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