Class NVBlendEquationAdvanced



  • public class NVBlendEquationAdvanced
    extends java.lang.Object
    Native bindings to the NV_blend_equation_advanced extension.

    This extension adds a number of "advanced" blending equations that can be used to perform new color blending operations, many of which are more complex than the standard blend modes provided by unextended OpenGL. This extension provides two different extension string entries:

    • NV_blend_equation_advanced: Provides the new blending equations, but guarantees defined results only if each sample is touched no more than once in any single rendering pass. The command BlendBarrierNV() is provided to indicate a boundary between passes.
    • NV_blend_equation_advanced_coherent: Provides the new blending equations, and guarantees that blending is done coherently and in API primitive ordering. An enable is provided to allow implementations to opt out of fully coherent blending and instead behave as though only NV_blend_equation_advanced were supported.

    Some implementations may support NV_blend_equation_advanced without supporting NV_blend_equation_advanced_coherent.

    In unextended OpenGL, the set of blending equations is limited, and can be expressed very simply. The MIN and MAX blend equations simply compute component-wise minimums or maximums of source and destination color components. The FUNC_ADD, FUNC_SUBTRACT, and FUNC_REVERSE_SUBTRACT multiply the source and destination colors by source and destination factors and either add the two products together or subtract one from the other. This limited set of operations supports many common blending operations but precludes the use of more sophisticated transparency and blending operations commonly available in many dedicated imaging APIs.

    This extension provides a number of new "advanced" blending equations. Unlike traditional blending operations using the FUNC_ADD equation, these blending equations do not use source and destination factors specified by BlendFunc. Instead, each blend equation specifies a complete equation based on the source and destination colors. These new blend equations are used for both RGB and alpha components; they may not be used to perform separate RGB and alpha blending (via functions like BlendEquationSeparate).

    These blending operations are performed using premultiplied colors, where RGB colors stored in the framebuffer are considered to be multiplied by alpha (coverage). The fragment color may be considered premultiplied or non-premultiplied, according the BLEND_PREMULTIPLIED_SRC_NV blending parameter (as specified by the new BlendParameteriNV function). If fragment color is considered non-premultiplied, the (R,G,B) color components are multiplied by the alpha component prior to blending. For non-premultiplied color components in the range [0,1], the corresponding premultiplied color component would have values in the range [0*A,1*A].

    Many of these advanced blending equations are formulated where the result of blending source and destination colors with partial coverage have three separate contributions: from the portions covered by both the source and the destination, from the portion covered only by the source, and from the portion covered only by the destination. The blend parameter BLEND_OVERLAP_NV can be used to specify a correlation between source and destination pixel coverage. If set to CONJOINT_NV, the source and destination are considered to have maximal overlap, as would be the case if drawing two objects on top of each other. If set to DISJOINT_NV, the source and destination are considered to have minimal overlap, as would be the case when rendering a complex polygon tessellated into individual non-intersecting triangles. If set to UNCORRELATED_NV (default), the source and destination coverage are assumed to have no spatial correlation within the pixel.

    In addition to the coherency issues on implementations not supporting NV_blend_equation_advanced_coherent, this extension has several limitations worth noting. First, the new blend equations are not supported while rendering to more than one color buffer at once; an INVALID_OPERATION will be generated if an application attempts to render any primitives in this unsupported configuration. Additionally, blending precision may be limited to 16-bit floating-point, which could result in a loss of precision and dynamic range for framebuffer formats with 32-bit floating-point components, and in a loss of precision for formats with 12- and 16-bit signed or unsigned normalized integer components.

    Requires GLES 2.0.

    • Field Detail

      • GL_BLEND_PREMULTIPLIED_SRC_NV

        public static final int GL_BLEND_PREMULTIPLIED_SRC_NV
        The BLEND_ADVANCED_COHERENT_NV enable is provided if and only if the NV_blend_equation_advanced_coherent extension is supported. On implementations supporting only NV_blend_equation_advanced, this enable is considered not to exist. Accepted by the pname parameter of BlendParameteriNV, GetBooleanv, GetIntegerv, GetInteger64v, GetFloatv, and GetDoublev.
        See Also:
        Constant Field Values
      • GL_BLEND_OVERLAP_NV

        public static final int GL_BLEND_OVERLAP_NV
        The BLEND_ADVANCED_COHERENT_NV enable is provided if and only if the NV_blend_equation_advanced_coherent extension is supported. On implementations supporting only NV_blend_equation_advanced, this enable is considered not to exist. Accepted by the pname parameter of BlendParameteriNV, GetBooleanv, GetIntegerv, GetInteger64v, GetFloatv, and GetDoublev.
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        Constant Field Values
      • GL_UNCORRELATED_NV

        public static final int GL_UNCORRELATED_NV
        Accepted by the value parameter of BlendParameteriNV when pname is BLEND_OVERLAP_NV.
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      • GL_DISJOINT_NV

        public static final int GL_DISJOINT_NV
        Accepted by the value parameter of BlendParameteriNV when pname is BLEND_OVERLAP_NV.
        See Also:
        Constant Field Values
      • GL_CONJOINT_NV

        public static final int GL_CONJOINT_NV
        Accepted by the value parameter of BlendParameteriNV when pname is BLEND_OVERLAP_NV.
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      • GL_SRC_NV

        public static final int GL_SRC_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_DST_NV

        public static final int GL_DST_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_SRC_OVER_NV

        public static final int GL_SRC_OVER_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_DST_OVER_NV

        public static final int GL_DST_OVER_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_SRC_IN_NV

        public static final int GL_SRC_IN_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_DST_IN_NV

        public static final int GL_DST_IN_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_SRC_OUT_NV

        public static final int GL_SRC_OUT_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_DST_OUT_NV

        public static final int GL_DST_OUT_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_SRC_ATOP_NV

        public static final int GL_SRC_ATOP_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_DST_ATOP_NV

        public static final int GL_DST_ATOP_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_XOR_NV

        public static final int GL_XOR_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_MULTIPLY_NV

        public static final int GL_MULTIPLY_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_SCREEN_NV

        public static final int GL_SCREEN_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_OVERLAY_NV

        public static final int GL_OVERLAY_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_DARKEN_NV

        public static final int GL_DARKEN_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
        Constant Field Values
      • GL_LIGHTEN_NV

        public static final int GL_LIGHTEN_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_COLORDODGE_NV

        public static final int GL_COLORDODGE_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_COLORBURN_NV

        public static final int GL_COLORBURN_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_HARDLIGHT_NV

        public static final int GL_HARDLIGHT_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_SOFTLIGHT_NV

        public static final int GL_SOFTLIGHT_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_DIFFERENCE_NV

        public static final int GL_DIFFERENCE_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_EXCLUSION_NV

        public static final int GL_EXCLUSION_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_INVERT_RGB_NV

        public static final int GL_INVERT_RGB_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_LINEARDODGE_NV

        public static final int GL_LINEARDODGE_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_LINEARBURN_NV

        public static final int GL_LINEARBURN_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_VIVIDLIGHT_NV

        public static final int GL_VIVIDLIGHT_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_LINEARLIGHT_NV

        public static final int GL_LINEARLIGHT_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_PINLIGHT_NV

        public static final int GL_PINLIGHT_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
        Constant Field Values
      • GL_HARDMIX_NV

        public static final int GL_HARDMIX_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
        Constant Field Values
      • GL_HSL_HUE_NV

        public static final int GL_HSL_HUE_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_HSL_SATURATION_NV

        public static final int GL_HSL_SATURATION_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_HSL_COLOR_NV

        public static final int GL_HSL_COLOR_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_HSL_LUMINOSITY_NV

        public static final int GL_HSL_LUMINOSITY_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_PLUS_NV

        public static final int GL_PLUS_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_PLUS_CLAMPED_NV

        public static final int GL_PLUS_CLAMPED_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_PLUS_CLAMPED_ALPHA_NV

        public static final int GL_PLUS_CLAMPED_ALPHA_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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        Constant Field Values
      • GL_PLUS_DARKER_NV

        public static final int GL_PLUS_DARKER_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
        Constant Field Values
      • GL_MINUS_NV

        public static final int GL_MINUS_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
        Constant Field Values
      • GL_MINUS_CLAMPED_NV

        public static final int GL_MINUS_CLAMPED_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
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      • GL_CONTRAST_NV

        public static final int GL_CONTRAST_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
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      • GL_INVERT_OVG_NV

        public static final int GL_INVERT_OVG_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
        Constant Field Values
      • GL_RED_NV

        public static final int GL_RED_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
        Constant Field Values
      • GL_GREEN_NV

        public static final int GL_GREEN_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
        Constant Field Values
      • GL_BLUE_NV

        public static final int GL_BLUE_NV
        Accepted by the mode parameter of BlendEquation and BlendEquationi.
        See Also:
        Constant Field Values
    • Method Detail

      • glBlendParameteriNV

        public static void glBlendParameteriNV(int pname,
                                               int value)
      • glBlendBarrierNV

        public static void glBlendBarrierNV()