glDepthRangeArray

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Specify mapping of depth values from normalized device coordinates to window coordinates for a specified set of viewports.

C Specification[edit]

void glDepthRangeArrayv( GLuint first, GLsizei count, const GLdouble * v );


Parameters[edit]

first - Specifies the index of the first viewport whose depth range to update.
count - Specifies the number of viewports whose depth range to update.
v - Specifies the address of an array containing the near and far values for the depth range of each modified viewport.


Description[edit]

After clipping and division byw, depth coordinates range from [math][/math] to 1, corresponding to the near and far clipping planes. Each viewport has an independent depth range specified as a linear mapping of the normalized depth coordinates in this range to window depth coordinates. Regardless of the actual depth buffer implementation, window coordinate depth values are treated as though they range from 0 through 1 (like color components). glDepthRangeArray specifies a linear mapping of the normalized depth coordinates in this range to window depth coordinates for each viewport in the range [ first , first + count ). Thus, the values accepted by glDepthRangeArray are both clamped to this range before they are accepted.

The first parameter specifies the index of the first viewport whose depth range to modify and must be less than the value of GL_MAX_VIEWPORTS . count specifies the number of viewports whose depth range to modify. first + count must be less than or equal to the value of GL_MAX_VIEWPORTS . v specifies the address of an array of pairs of double precision floating point values representing the near and far values of the depth range for each viewport, in that order.

The setting of (0,1) maps the near plane to 0 and the far plane to 1. With this mapping, the depth buffer range is fully utilized.


Notes[edit]

It is not necessary that the near plane distance be less than the far plane distance. Reverse mappings such as [math]near=1[/math] , and [math]far=0[/math] are acceptable.

The type of the v parameter was changed from GLclampd to GLdouble. This change is transparent to user code and is described in detail on the removedTypes page.


Errors[edit]

 GL_INVALID_VALUE is generated if first is greater than or equal to the value of GL_MAX_VIEWPORTS .

 GL_INVALID_VALUE is generated if first + count is greater than or equal to the value of GL_MAX_VIEWPORTS .


Associated Gets[edit]

 glGet with argument GL_DEPTH_RANGE 


Version Support[edit]

 glDepthRangeArrayv  4.1+

See Also[edit]

 glDepthFunc , glDepthRange , glDepthRangeIndexed , glPolygonOffset , glViewportArray , glViewport , removedTypes 


Copyright[edit]

Copyright© 2010-2014 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999. http://opencontent.org/openpub/.