org.lwjgl.opengl.NVConditionalRender Maven / Gradle / Ivy

/*
 * Copyright LWJGL. All rights reserved.
 * License terms: https://www.lwjgl.org/license
 * MACHINE GENERATED FILE, DO NOT EDIT
 */
package org.lwjgl.opengl;

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

/**
 * Native bindings to the NV_conditional_render extension.
 * 
 * This extension provides support for conditional rendering based on the results of an occlusion query. This mechanism allows an application to
 * potentially reduce the latency between the completion of an occlusion query and the rendering commands depending on its result. It additionally allows
 * the decision of whether to render to be made without application intervention.
 * 
 * This extension defines two new functions, {@link #glBeginConditionalRenderNV BeginConditionalRenderNV} and {@link #glEndConditionalRenderNV EndConditionalRenderNV}, between which rendering commands may be discarded
 * based on the results of an occlusion query. If the specified occlusion query returns a non-zero value, rendering commands between these calls are
 * executed. If the occlusion query returns a value of zero, all rendering commands between the calls are discarded.
 * 
 * If the occlusion query results are not available when {@link #glBeginConditionalRenderNV BeginConditionalRenderNV} is executed, the {@code mode} parameter specifies whether the GL
 * should wait for the query to complete or should simply render the subsequent geometry unconditionally.
 * 
 * Additionally, the extension provides a set of "by region" modes, allowing for implementations that divide rendering work by screen regions to perform
 * the conditional query test on a region-by-region basis without checking the query results from other regions. Such a mode is useful for cases like
 * split-frame SLI, where a frame is divided between multiple GPUs, each of which has its own occlusion query hardware.
 */
public class NVConditionalRender {

    /** Accepted by the {@code mode} parameter of BeginConditionalRenderNV. */
    public static final int
        GL_QUERY_WAIT_NV              = 0x8E13,
        GL_QUERY_NO_WAIT_NV           = 0x8E14,
        GL_QUERY_BY_REGION_WAIT_NV    = 0x8E15,
        GL_QUERY_BY_REGION_NO_WAIT_NV = 0x8E16;

    static { GL.initialize(); }

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

    static boolean isAvailable(GLCapabilities caps) {
        return checkFunctions(
            caps.glBeginConditionalRenderNV, caps.glEndConditionalRenderNV
        );
    }

    // --- [ glBeginConditionalRenderNV ] ---

    public static native void glBeginConditionalRenderNV(int id, int mode);

    // --- [ glEndConditionalRenderNV ] ---

    public static native void glEndConditionalRenderNV();

}