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A royalty-free, cross-platform API for full-function 2D and 3D graphics on embedded systems - including consoles, phones, appliances and vehicles.
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/*
 * Copyright LWJGL. All rights reserved.
 * License terms: https://www.lwjgl.org/license
 * MACHINE GENERATED FILE, DO NOT EDIT
 */
package org.lwjgl.opengles;

import static org.lwjgl.system.Checks.*;

/**
 * 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.
 */
public class NVCoverageSample {

    /** Accepted by the {@code internalformat} parameter of RenderbufferStorageEXT and the {@code format} parameter of ReadPixels. */
    public static final int GL_COVERAGE_COMPONENT_NV = 0x8ED0;

    /** Accepted by the {@code internalformat} parameter of RenderbufferStorageEXT. */
    public static final int GL_COVERAGE_COMPONENT4_NV = 0x8ED1;

    /** Accepted by the {@code operation} parameter of CoverageOperationNV. */
    public static final int
        GL_COVERAGE_ALL_FRAGMENTS_NV  = 0x8ED5,
        GL_COVERAGE_EDGE_FRAGMENTS_NV = 0x8ED6,
        GL_COVERAGE_AUTOMATIC_NV      = 0x8ED7;

    /** Accepted by the {@code attachment} parameter of FramebufferRenderbuffer, and GetFramebufferAttachmentParameteriv. */
    public static final int GL_COVERAGE_ATTACHMENT_NV = 0x8ED2;

    /** Accepted by the {@code buf} parameter of Clear. */
    public static final int GL_COVERAGE_BUFFER_BIT_NV = 0x8000;

    /** Accepted by the {@code pname} parameter of GetIntegerv. */
    public static final int
        GL_COVERAGE_BUFFERS_NV = 0x8ED3,
        GL_COVERAGE_SAMPLES_NV = 0x8ED4;

    static { GLES.initialize(); }

    protected NVCoverageSample() {
        throw new UnsupportedOperationException();
    }

    static boolean isAvailable(GLESCapabilities caps) {
        return checkFunctions(
            caps.glCoverageMaskNV, caps.glCoverageOperationNV
        );
    }

    // --- [ glCoverageMaskNV ] ---

    public static native void glCoverageMaskNV(boolean mask);

    // --- [ glCoverageOperationNV ] ---

    public static native void glCoverageOperationNV(int operation);

}