Class EXTWindowRectangles



  • public class EXTWindowRectangles
    extends java.lang.Object
    Native bindings to the EXT_window_rectangles extension.

    This extension provides additional orthogonally aligned "window rectangles" specified in window-space coordinates that restrict rasterization of all primitive types (geometry, images, paths) and framebuffer clears.

    When rendering to the framebuffer of an on-screen window, these window rectangles are ignored so these window rectangles apply to rendering to non-zero framebuffer objects only.

    From zero to an implementation-dependent limit (specified by MAX_WINDOW_RECTANGLES_EXT) number of window rectangles can be operational at once. When one or more window rectangles are active, rasterized fragments can either survive if the fragment is within any of the operational window rectangles (INCLUSIVE_EXT mode) or be rejected if the fragment is within any of the operational window rectangles (EXCLUSIVE_EXT mode).

    These window rectangles operate orthogonally to the existing scissor test functionality.

    This extension has specification language for both OpenGL and ES so EXT_window_rectangles can be implemented and advertised for either or both API contexts.

    Requires GL30 or EXT_draw_buffers2.

    • Method Detail

      • glWindowRectanglesEXT

        public static void glWindowRectanglesEXT(int mode,
                                                 java.nio.IntBuffer box)
        Sets the active window rectangles.

        When the WindowRectanglesEXT command is processed without error, the ith window rectangle box is set to the corresponding four parameters for values of i less then n. For values of i greater than n, each window rectangle box is set to (0,0,0,0).

        Each four elements corresponds to the ith window rectangle indicating a box of pixels specified with window-space coordinates. Each window rectangle box i has a lower-left origin at (x_i,y_i) and upper-right corner at (x_i+w_i,y_i+h_i).

        The INVALID_VALUE error is generated if any element w_i or h_i, corresponding to each box's respective width and height, is negative.

        Each rasterized or cleared fragment with a window-space position (xw,yw) is within the ith window rectangle box when both of these equations are satisfied for all i less than n:

        x_i <= xw < x_i+w_i
        y_i <= yw < y_i+h_i

        When the window rectangles mode is INCLUSIVE_EXT mode and the bound framebuffer object is non-zero, a fragment passes the window rectangles test if the fragment's window-space position is within at least one of the current n active window rectangles; otherwise the window rectangles test fails and the fragment is discarded.

        When the window rectangles mode is EXCLUSIVE_EXT mode and the bound framebuffer object is non-zero, a fragment fails the window rectangles test and is discarded if the fragment's window-space position is within at least one of the current n active window rectangles; otherwise the window rectangles test passes and the fragment passes the window rectangles test.

        When the bound framebuffer object is zero, the window rectangles test always passes.

        Parameters:
        mode - the rectangle mode. One of:
        INCLUSIVE_EXTEXCLUSIVE_EXT
        box - an array of 4*count window rectangle coordinates
      • glWindowRectanglesEXT

        public static void glWindowRectanglesEXT(int mode,
                                                 int[] box)
        Array version of: WindowRectanglesEXT