LWJGL 3.3.3 · org.lwjgl.opengl.OVRMultiview

public Class OVRMultiview

extends Object

Class Inheritance

java.lang.Object
org.lwjgl.opengl.OVRMultiview

Imports

org.lwjgl.system.*

Native bindings to the OVR_multiview extension.

The method of stereo rendering supported in OpenGL is currently achieved by rendering to the two eye buffers sequentially. This typically incurs double the application and driver overhead, despite the fact that the command streams and render states are almost identical.

This extension seeks to address the inefficiency of sequential multiview rendering by adding a means to render to multiple elements of a 2D texture array simultaneously. In multiview rendering, draw calls are instanced into each corresponding element of the texture array. The vertex program uses a new gl_ViewID_OVR variable to compute per-view values, typically the vertex position and view-dependent variables like reflection.

The formulation of this extension is high level in order to allow implementation freedom. On existing hardware, applications and drivers can realize the benefits of a single scene traversal, even if all GPU work is fully duplicated per-view. But future support could enable simultaneous rendering via multi-GPU, tile-based architectures could sort geometry into tiles for multiple views in a single pass, and the implementation could even choose to interleave at the fragment level for better texture cache utilization and more coherent fragment shader branching.

The most obvious use case in this model is to support two simultaneous views: one view for each eye. However, we also anticipate a usage where two views are rendered per eye, where one has a wide field of view and the other has a narrow one. The nature of wide field of view planar projection is that the sample density can become unacceptably low in the view direction. By rendering two inset eye views per eye, we can get the required sample density in the center of projection without wasting samples, memory, and time by oversampling in the periphery.

Requires OpenGL 3.0.

Modifier and Type	Field and Description
public static final int	GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_BASE_VIEW_INDEX_OVR Accepted by the `pname` parameter of `GetFramebufferAttachmentParameteriv`.
public static final int	GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_NUM_VIEWS_OVR Accepted by the `pname` parameter of `GetFramebufferAttachmentParameteriv`.
public static final int	GL_FRAMEBUFFER_INCOMPLETE_VIEW_TARGETS_OVR Returned by `CheckFramebufferStatus`.
public static final int	GL_MAX_VIEWS_OVR Accepted by the `pname` parameter of GetIntegerv.

Modifier and Type

Field and Description

public static final int

GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_BASE_VIEW_INDEX_OVR

Accepted by the pname parameter of GetFramebufferAttachmentParameteriv.

public static final int

GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_NUM_VIEWS_OVR

Accepted by the pname parameter of GetFramebufferAttachmentParameteriv.

public static final int

GL_FRAMEBUFFER_INCOMPLETE_VIEW_TARGETS_OVR

Returned by CheckFramebufferStatus.

public static final int

GL_MAX_VIEWS_OVR

Accepted by the pname parameter of GetIntegerv.

Constructor Summary

Access	Constructor and Description
protected	OVRMultiview()

Field Detail

GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_BASE_VIEW_INDEX_OVR	back to summary
public static final int GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_BASE_VIEW_INDEX_OVR Accepted by the `pname` parameter of `GetFramebufferAttachmentParameteriv`.

GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_NUM_VIEWS_OVR	back to summary
public static final int GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_NUM_VIEWS_OVR Accepted by the `pname` parameter of `GetFramebufferAttachmentParameteriv`.

GL_FRAMEBUFFER_INCOMPLETE_VIEW_TARGETS_OVR	back to summary
public static final int GL_FRAMEBUFFER_INCOMPLETE_VIEW_TARGETS_OVR Returned by `CheckFramebufferStatus`.

GL_MAX_VIEWS_OVR	back to summary
public static final int GL_MAX_VIEWS_OVR Accepted by the `pname` parameter of GetIntegerv.

Constructor Detail

OVRMultiview	back to summary
protected OVRMultiview()

Method Detail

glFramebufferTextureMultiviewOVR back to summary

public static native void glFramebufferTextureMultiviewOVR(int target, int attachment, int texture, int level, int baseViewIndex, int numViews)

Operates similarly to the FramebufferTextureLayer command, except that baseViewIndex and numViews select a range of texture array elements that will be targeted when rendering. Such an attachment is considered multiview and rendering commands issued when such a framebuffer object is bound are termed "multiview rendering". The maximum number of views which can be bound simultaneously is determined by the value of MAX_VIEWS_OVR, which can be queried with the GetIntegerv command.

The command


View( uint id );

does not exist in the GL, but is used here to describe the multiview functionality in this section. The effect of this hypothetical function is to set the value of the shader built-in input gl_ViewID_OVR.

When multiview rendering is enabled, the Clear, ClearBuffer*, Draw*, and Dispatch* commands have the same effect as:


for( int i = 0; i < numViews; i++ ) {
    FramebufferTextureLayer( target, attachment, texture, level, baseViewIndex + i );
    View( i );
    <drawing-command>
}

The result is that every drawing command is broadcast into every active view. The shader uses gl_ViewID_OVR to compute view dependent outputs.

The number of views, as specified by numViews, must be the same for all framebuffer attachments points where the value of FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE is not NONE or the framebuffer is incomplete.

If texture is non-zero and the command does not result in an error, the framebuffer attachment state corresponding to attachment is updated as in the FramebufferTextureLayer command, except that the values of FRAMEBUFFER_ATTACHMENT_TEXTURE_LAYER and FRAMEBUFFER_ATTACHMENT_TEXTURE_BASE_VIEW_INDEX_OVR are is set to baseViewIndex, and the value of FRAMEBUFFER_ATTACHMENT_TEXTURE_NUM_VIEWS_OVR is set to numViews.

Errors

In addition to the corresponding errors for FramebufferTextureLayer when called with the same parameters (other than layer):

An INVALID_VALUE error is generated if:

numViews is less than 1 or if numViews is greater than MAX_VIEWS_OVR.
texture is a two-dimensional array texture and baseViewIndex + numViews is larger than the value of MAX_ARRAY_TEXTURE_LAYERS minus one.
texture is non-zero and baseViewIndex is negative.

An INVALID_OPERATION error is generated if texture is non-zero and is not the name of a two-dimensional array texture.

Parameters

target:int

the framebuffer target. One of:

FRAMEBUFFER

READ_FRAMEBUFFER

DRAW_FRAMEBUFFER

attachment:int

the attachment point of the framebuffer. One of:

`COLOR_ATTACHMENT0`	`COLOR_ATTACHMENT1`	`COLOR_ATTACHMENT2`	`COLOR_ATTACHMENT3`
`COLOR_ATTACHMENT4`	`COLOR_ATTACHMENT5`	`COLOR_ATTACHMENT6`	`COLOR_ATTACHMENT7`
`COLOR_ATTACHMENT8`	`COLOR_ATTACHMENT9`	`COLOR_ATTACHMENT10`	`COLOR_ATTACHMENT11`
`COLOR_ATTACHMENT12`	`COLOR_ATTACHMENT13`	`COLOR_ATTACHMENT14`	`COLOR_ATTACHMENT15`
`COLOR_ATTACHMENT16`	`COLOR_ATTACHMENT17`	`COLOR_ATTACHMENT18`	`COLOR_ATTACHMENT19`
`COLOR_ATTACHMENT20`	`COLOR_ATTACHMENT21`	`COLOR_ATTACHMENT22`	`COLOR_ATTACHMENT23`
`COLOR_ATTACHMENT24`	`COLOR_ATTACHMENT25`	`COLOR_ATTACHMENT26`	`COLOR_ATTACHMENT27`
`COLOR_ATTACHMENT28`	`COLOR_ATTACHMENT29`	`COLOR_ATTACHMENT30`	`COLOR_ATTACHMENT31`
`DEPTH_ATTACHMENT`	`STENCIL_ATTACHMENT`	`DEPTH_STENCIL_ATTACHMENT`

texture:int

the texture object to attach to the framebuffer attachment point named by attachment

level:int

the mipmap level of texture to attach

baseViewIndex:int

the base framebuffer texture layer index

numViews:int

the number of views to target when rendering

glNamedFramebufferTextureMultiviewOVR back to summary

public static native void glNamedFramebufferTextureMultiviewOVR(int framebuffer, int attachment, int texture, int level, int baseViewIndex, int numViews)

Parameters

framebuffer:int

the framebuffer name

attachment:int

the attachment point of the framebuffer. One of:

`COLOR_ATTACHMENT0`	`COLOR_ATTACHMENT1`	`COLOR_ATTACHMENT2`	`COLOR_ATTACHMENT3`
`COLOR_ATTACHMENT4`	`COLOR_ATTACHMENT5`	`COLOR_ATTACHMENT6`	`COLOR_ATTACHMENT7`
`COLOR_ATTACHMENT8`	`COLOR_ATTACHMENT9`	`COLOR_ATTACHMENT10`	`COLOR_ATTACHMENT11`
`COLOR_ATTACHMENT12`	`COLOR_ATTACHMENT13`	`COLOR_ATTACHMENT14`	`COLOR_ATTACHMENT15`
`COLOR_ATTACHMENT16`	`COLOR_ATTACHMENT17`	`COLOR_ATTACHMENT18`	`COLOR_ATTACHMENT19`
`COLOR_ATTACHMENT20`	`COLOR_ATTACHMENT21`	`COLOR_ATTACHMENT22`	`COLOR_ATTACHMENT23`
`COLOR_ATTACHMENT24`	`COLOR_ATTACHMENT25`	`COLOR_ATTACHMENT26`	`COLOR_ATTACHMENT27`
`COLOR_ATTACHMENT28`	`COLOR_ATTACHMENT29`	`COLOR_ATTACHMENT30`	`COLOR_ATTACHMENT31`
`DEPTH_ATTACHMENT`	`STENCIL_ATTACHMENT`	`DEPTH_STENCIL_ATTACHMENT`

texture:int

the texture object to attach to the framebuffer attachment point named by attachment

level:int

the mipmap level of texture to attach

public Class OVRMultiview

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail

Errors