java.lang.Object
- org.lwjgl.opengles.NVCoverageSample

```
public class NVCoverageSample
extends java.lang.Object
```
Native bindings to the NV_coverage_sample extension.
Anti-aliasing is a critical component for delivering high-quality OpenGL rendering. Traditionally, OpenGL implementations have implemented two anti-aliasing algorithms: edge anti-aliasing and multisampling.

Edge anti-aliasing computes fractional fragment coverage for all primitives in a rendered frame, and blends edges of abutting and/or overlapping primitives to produce smooth results. The image quality produced by this approach is exceptionally high; however, applications are render their geometry perfectly ordered back-to-front in order to avoid artifacts such as bleed-through. Given the algorithmic complexity and performance cost of performing exact geometric sorts, edge anti-aliasing has been used very sparingly, and almost never in interactive games.

Multisampling, on the other hand, computes and stores subpixel (a.k.a. "sample") coverage for rasterized fragments, and replicates all post-alpha test operations (e.g., depth test, stencil test, alpha blend) for each sample. After the entire scene is rendered, the samples are filtered to compute the final anti-aliased image. Because the post-alpha test operations are replicated for each sample, all of the bleed-through and ordering artifacts that could occur with edge anti-aliasing are avoided completely; however, since each sample must be computed and stored separately, anti-aliasing quality is limited by framebuffer storage and rendering performance.

This extension introduces a new anti-aliasing algorithm to OpenGL, which dramatically improves multisampling quality without adversely affecting multisampling's robustness or significantly increasing the storage required, coverage sampling.

Coverage sampling adds an additional high-precision geometric coverage buffer to the framebuffer, which is used to produce high-quality filtered results (with or without the presence of a multisample buffer). This coverage information is computed and stored during rasterization; since applications may render objects where the specified geometry does not correspond to the visual result (examples include alpha-testing for "imposters," or extruded volume rendering for stencil shadow volumes), coverage buffer updates may be masked by the application, analagous to masking the depth buffer.

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`GL_COVERAGE_ALL_FRAGMENTS_NV` Accepted by the `operation` parameter of CoverageOperationNV.
`static int`	`GL_COVERAGE_ATTACHMENT_NV` Accepted by the `attachment` parameter of FramebufferRenderbuffer, and GetFramebufferAttachmentParameteriv.
`static int`	`GL_COVERAGE_AUTOMATIC_NV` Accepted by the `operation` parameter of CoverageOperationNV.
`static int`	`GL_COVERAGE_BUFFER_BIT_NV` Accepted by the `buf` parameter of Clear.
`static int`	`GL_COVERAGE_BUFFERS_NV` Accepted by the `pname` parameter of GetIntegerv.
`static int`	`GL_COVERAGE_COMPONENT_NV` Accepted by the `internalformat` parameter of RenderbufferStorageEXT and the `format` parameter of ReadPixels.
`static int`	`GL_COVERAGE_COMPONENT4_NV` Accepted by the `internalformat` parameter of RenderbufferStorageEXT.
`static int`	`GL_COVERAGE_EDGE_FRAGMENTS_NV` Accepted by the `operation` parameter of CoverageOperationNV.
`static int`	`GL_COVERAGE_SAMPLES_NV` Accepted by the `pname` parameter of GetIntegerv.

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type Method and Description

static void glCoverageMaskNV(boolean mask)

static void glCoverageOperationNV(int operation)
- Methods inherited from class java.lang.Object
  equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - GL_COVERAGE_COMPONENT_NV
```
public static final int GL_COVERAGE_COMPONENT_NV
```
    Accepted by the internalformat parameter of RenderbufferStorageEXT and the format parameter of ReadPixels.
    
    See Also:
    
    Constant Field Values
  - GL_COVERAGE_COMPONENT4_NV
```
public static final int GL_COVERAGE_COMPONENT4_NV
```
    Accepted by the internalformat parameter of RenderbufferStorageEXT.
    
    See Also:
    
    Constant Field Values
  - GL_COVERAGE_ALL_FRAGMENTS_NV
```
public static final int GL_COVERAGE_ALL_FRAGMENTS_NV
```
    Accepted by the operation parameter of CoverageOperationNV.
    
    See Also:
    
    Constant Field Values
  - GL_COVERAGE_EDGE_FRAGMENTS_NV
```
public static final int GL_COVERAGE_EDGE_FRAGMENTS_NV
```
    Accepted by the operation parameter of CoverageOperationNV.
    
    See Also:
    
    Constant Field Values
  - GL_COVERAGE_AUTOMATIC_NV
```
public static final int GL_COVERAGE_AUTOMATIC_NV
```
    Accepted by the operation parameter of CoverageOperationNV.
    
    See Also:
    
    Constant Field Values
  - GL_COVERAGE_ATTACHMENT_NV
```
public static final int GL_COVERAGE_ATTACHMENT_NV
```
    Accepted by the attachment parameter of FramebufferRenderbuffer, and GetFramebufferAttachmentParameteriv.
    
    See Also:
    
    Constant Field Values
  - GL_COVERAGE_BUFFER_BIT_NV
```
public static final int GL_COVERAGE_BUFFER_BIT_NV
```
    Accepted by the buf parameter of Clear.
    
    See Also:
    
    Constant Field Values
  - GL_COVERAGE_BUFFERS_NV
```
public static final int GL_COVERAGE_BUFFERS_NV
```
    Accepted by the pname parameter of GetIntegerv.
    
    See Also:
    
    Constant Field Values
  - GL_COVERAGE_SAMPLES_NV
```
public static final int GL_COVERAGE_SAMPLES_NV
```
    Accepted by the pname parameter of GetIntegerv.
    
    See Also:
    
    Constant Field Values
- Method Detail
  - glCoverageMaskNV
```
public static void glCoverageMaskNV(boolean mask)
```
  - glCoverageOperationNV
```
public static void glCoverageOperationNV(int operation)
```

Modifier and Type	Method and Description
`static void`	`glCoverageMaskNV(boolean mask)`
`static void`	`glCoverageOperationNV(int operation)`

Class NVCoverageSample

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

GL_COVERAGE_COMPONENT_NV

GL_COVERAGE_COMPONENT4_NV

GL_COVERAGE_ALL_FRAGMENTS_NV

GL_COVERAGE_EDGE_FRAGMENTS_NV

GL_COVERAGE_AUTOMATIC_NV

GL_COVERAGE_ATTACHMENT_NV

GL_COVERAGE_BUFFER_BIT_NV

GL_COVERAGE_BUFFERS_NV

GL_COVERAGE_SAMPLES_NV

Method Detail

glCoverageMaskNV

glCoverageOperationNV