| Name |
| |
| NV_render_texture_rectangle |
| |
| Name Strings |
| |
| WGL_NV_render_texture_rectangle |
| |
| Contact |
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| Pat Brown, NVIDIA Corporation (pbrown 'at' nvidia.com) |
| |
| Notice |
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| Copyright NVIDIA Corporation, 2001, 2002. |
| |
| Status |
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| Shipping, March 2002. |
| |
| Version |
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| Last Modified Date: 2003/01/08 |
| NVIDIA Revision: 7 |
| |
| Number |
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| 264 |
| |
| Dependencies |
| |
| OpenGL 1.1 is required. |
| |
| WGL_ARB_render_texture is required. |
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| GL_NV_texture_rectangle is required. |
| |
| The extension is written against the OpenGL 1.2.1 Specification. |
| |
| Overview |
| |
| This extension allows a color buffer with non-power-of-two dimensions to |
| be used for both rendering and texturing. It is built upon the |
| ARB_render_texture extension; the only addition in this extension is the |
| ability to bind a texture to a texture rectangle target, as provided |
| through the NV_texture_rectangle extension. |
| |
| Issues |
| |
| What is the interaction of this spec and the WGL_MIPMAP_TEXTURE_ARB |
| attribute? |
| |
| RESOLVED: NV_texture_rectangle doesn't support mipmaps, so it's kind of |
| stupid to allocate them. Trying will result in an error. |
| |
| Should there be separate pixel format attributes for |
| BIND_TO_TEXTURE_RECTANGLE_RGB and RGBA? Or is a simple |
| BIND_TO_TEXTURE_RECTANGLE attribute sufficient? |
| |
| RESOLVED: Separate capabilities. There may be pixel formats where |
| rendered texture rectangles are supported, but conventional textures are |
| not. If a single BIND_TO_TEXTURE_RECTANGLE attribute were used, there |
| would be no cue for RGB/RGBA binding support, and the existing |
| attributes would signal the ability to render to conventional textures. |
| |
| Alternately, pixel formats could be constrained so that the only |
| render-texture capable formats are those that support all allowable |
| targets. |
| |
| Implementation Notes |
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| None. |
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| New Procedures and Functions |
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| None. |
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| New Tokens |
| |
| Accepted by the <piAttributes> parameter of wglGetPixelFormatAttribivARB, |
| wglGetPixelFormatAttribfvARB, and the <piAttribIList> and <pfAttribIList> |
| parameters of wglChoosePixelFormatARB: |
| |
| WGL_BIND_TO_TEXTURE_RECTANGLE_RGB_NV 0x20A0 |
| WGL_BIND_TO_TEXTURE_RECTANGLE_RGBA_NV 0x20A1 |
| |
| Accepted as a value in the <piAttribList> parameter of wglCreatePbufferARB |
| and returned in the value parameter of wglQueryPbufferARB when |
| <iAttribute> is WGL_TEXTURE_TARGET_ARB: |
| |
| WGL_TEXTURE_RECTANGLE_NV 0x20A2 |
| |
| Additions to Chapter 2 of the OpenGL 1.2.1 Specification (OpenGL Operation) |
| |
| None. |
| |
| Additions to Chapter 3 of the OpenGL 1.2.1 Specification (Rasterization) |
| |
| None. |
| |
| Additions to Chapter 4 of the OpenGL 1.2.1 Specification (Per-Fragment |
| Operations and the Frame Buffer) |
| |
| None. |
| |
| Additions to Chapter 5 of the OpenGL 1.2.1 Specification (Special Functions) |
| |
| None. |
| |
| Additions to Chapter 6 of the OpenGL 1.2.1 Specification (State and State |
| Requests) |
| |
| None. |
| |
| Additions to the WGL Specification |
| |
| First, close your eyes and pretend that a WGL specification actually |
| existed. Maybe if we all concentrate hard enough, one will magically |
| appear. |
| |
| These modifications are relative to the ARB_render_texture spec. |
| |
| Add to the description of <piAttributes> in wglGetPixelFormatAttribivARB |
| and <pfAttributes> in wglGetPixelFormatfv: |
| |
| WGL_BIND_TO_TEXTURE_RECTANGLE_RGB_NV |
| WGL_BIND_TO_TEXTURE_RECTANGLE_RGBA_NV |
| |
| True if the color buffers can be bound as RGB/RGBA textures using the |
| texture rectangle target. Currently only pbuffers can be bound as |
| textures so this attribute will only be TRUE if WGL_DRAW_TO_PBUFFER is |
| also TRUE. It is possible to bind a RGBA visual to a RGB texture in |
| which case the values in the alpha component of the visual are ignored |
| when the color buffer is used as a RGB texture. |
| |
| Add new table entries to match criteria in description of |
| wglChoosePixelFormatARB: |
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| Attribute Type Match Criteria |
| |
| WGL_BIND_TO_TEXTURE_RECTANGLE_RGB_NV boolean exact |
| WGL_BIND_TO_TEXTURE_RECTANGLE_RGBA_NV boolean exact |
| |
| Modify wglCreatePbufferARB: |
| |
| The following attributes are supported by wglCreatePbufferARB: |
| |
| ... |
| |
| WGL_TEXTURE_TARGET_ARB |
| |
| This attribute indicates the target for the texture that will be |
| created when the pbuffer is created with a texture format other than |
| WGL_NO_TEXTURE_ARB. This attribute can be set to WGL_NO_TEXTURE_ARB, |
| WGL_TEXTURE_1D_ARB, WGL_TEXTURE_2D_ARB, WGL_TEXTURE_CUBE_MAP_ARB, or |
| WGL_TEXTURE_RECTANGLE_NV. The default value is WGL_NO_TEXTURE_ARB. |
| |
| (Modify power-of-two error for wglCreatePbufferARB) |
| |
| ERROR_INVALID_DATA The pixel format attribute |
| WGL_TEXTURE_TARGET_ARB is WGL_TEXTURE_1D_ARB, |
| WGL_TEXTURE_2D_ARB, or |
| WGL_TEXTURE_CUBE_MAP_ARB, and WGL_PBUFFER_WIDTH |
| and/or WGL_PBUFFER_HEIGHT is not a power of |
| two. |
| |
| (Add new wglCreatePbufferARB error) |
| |
| ERROR_INVALID_DATA WGL_TEXTURE_TARGET_ARB is |
| WGL_TEXTURE_RECTANGLE_NV |
| and WGL_MIPMAP_TEXTURE_ARB is non-zero. |
| |
| (Add wglCreatePbufferARB errors missing from the ARB_render_texture spec) |
| |
| ERROR_INVALID_DATA WGL_TEXTURE_FORMAT_ARB is WGL_TEXTURE_RGB_NV, |
| WGL_TEXTURE_TARGET_ARB is |
| WGL_TEXTURE_RECTANGLE_NV, and the |
| WGL_BIND_TO_TEXTURE_RECTANGLE_RGB_NV attribute |
| is not set in the pixel format. |
| |
| ERROR_INVALID_DATA WGL_TEXTURE_FORMAT_ARB is WGL_TEXTURE_RGB_NV, |
| WGL_TEXTURE_TARGET_ARB is not |
| WGL_TEXTURE_RECTANGLE_NV, and the |
| WGL_BIND_TO_TEXTURE_RGB_NV attribute is not set |
| in the pixel format. |
| |
| ERROR_INVALID_DATA WGL_TEXTURE_FORMAT_ARB is WGL_TEXTURE_RGBA_NV, |
| WGL_TEXTURE_TARGET_ARB is |
| WGL_TEXTURE_RECTANGLE_NV, and the |
| WGL_BIND_TO_TEXTURE_RECTANGLE_RGBA_NV attribute |
| is not set in the pixel format. |
| |
| ERROR_INVALID_DATA WGL_TEXTURE_FORMAT_ARB is WGL_TEXTURE_RGBA_NV, |
| WGL_TEXTURE_TARGET_ARB is not |
| WGL_TEXTURE_RECTANGLE_NV, and the |
| WGL_BIND_TO_TEXTURE_RGBA_NV attribute is not |
| set in the pixel format. |
| |
| Modify wglBindTexImageARB (only adding verbiage for supporting texture |
| rectangles): |
| |
| The command |
| |
| BOOL wglBindTexImageARB (HPBUFFERARB hPbuffer, int iBuffer) |
| |
| defines a one-dimensional texture image, a two-dimensional |
| texture image, a two-dimensional texture rectangle image, or a set of |
| two-dimensional cube map texture images... |
| |
| The texture targets are derived... If the texture target is |
| WGL_TEXTURE_2D_ARB, then <iBuffer> defines a 2D texture for the |
| current 2D texture object. If the texture target is |
| WGL_TEXTURE_RECTANGLE_NV, then <iBuffer> defines a texture rectangle |
| for the current texture rectangle object. If the texture target is |
| WGL_TEXTURE_1D_ARB, then <iBuffer> defines a 1D texture for the |
| current 1D texture object. |
| |
| |
| New State |
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| None |
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| Revision History |
| |
| None |
