text: /*
   * Copyright (c) 2003, 2019, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
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   */
  
  #ifndef OGLSurfaceData_h_Included
  #define OGLSurfaceData_h_Included
  
  #include "java_awt_image_AffineTransformOp.h"
  #include "sun_java2d_opengl_OGLSurfaceData.h"
  #include "sun_java2d_pipe_hw_AccelSurface.h"
  
  #include "J2D_GL/gl.h"
  #include "SurfaceData.h"
  #include "Trace.h"
  #include "OGLFuncs.h"
  
  typedef struct _OGLSDOps OGLSDOps;
  
  /**
   * The OGLPixelFormat structure contains all the information OpenGL needs to
   * know when copying from or into a particular system memory image buffer (via
   * glDrawPixels(), glReadPixels, glTexSubImage2D(), etc).
   *
   *     GLenum format;
   * The pixel format parameter used in glDrawPixels() and other similar calls.
   * Indicates the component ordering for each pixel (e.g. GL_BGRA).
   *
   *     GLenum type;
   * The pixel data type parameter used in glDrawPixels() and other similar
   * calls.  Indicates the data type for an entire pixel or for each component
   * in a pixel (e.g. GL_UNSIGNED_BYTE with GL_BGR means a pixel consists of
   * 3 unsigned byte components, blue first, then green, then red;
   * GL_UNSIGNED_INT_8_8_8_8_REV with GL_BGRA means a pixel consists of 1
   * unsigned integer comprised of four byte components, alpha first, then red,
   * then green, then blue).
   *
   *     jint alignment;
   * The byte alignment parameter used in glPixelStorei(GL_UNPACK_ALIGNMENT).  A
   * value of 4 indicates that each pixel starts on a 4-byte aligned region in
   * memory, and so on.  This alignment parameter helps OpenGL speed up pixel
   * transfer operations by transferring memory in aligned blocks.
   *
   *     jboolean hasAlpha;
   * If true, indicates that this pixel format contains an alpha component.
   *
   *     jboolean isPremult;
   * If true, indicates that this pixel format contains color components that
   * have been pre-multiplied by their corresponding alpha component.
   */
  typedef struct {
      GLenum   format;
      GLenum   type;
      jint     alignment;
      jboolean hasAlpha;
      jboolean isPremult;
  } OGLPixelFormat;
  
  /**
   * The OGLSDOps structure describes a native OpenGL surface and contains all
   * information pertaining to the native surface.  Some information about
   * the more important/different fields:
   *
   *     void *privOps;
   * Pointer to native-specific (GLX, WGL, etc.) SurfaceData info, such as the
   * native Drawable handle and GraphicsConfig data.
   *
   *     jobject graphicsConfig;;
   * Strong reference to the OGLGraphicsConfig used by this OGLSurfaceData.
   *
   *     jint drawableType;
   * The surface type; can be any one of the surface type constants defined
   * below (OGLSD_WINDOW, OGLSD_TEXTURE, etc).
   *
   *     GLenum activeBuffer;
   * Can be either GL_FRONT if this is the front buffer surface of an onscreen
   * window or a pbuffer surface, or GL_BACK if this is the backbuffer surface
   * of an onscreen window.
   *
   *     jboolean isOpaque;
   * If true, the surface should be treated as being fully opaque.  If
   * the underlying surface (e.g. pbuffer) has an alpha channel and isOpaque
   * is true, then we should take appropriate action (i.e. call glColorMask()
   * to disable writes into the alpha channel) to ensure that the surface
   * remains fully opaque.
   *
   *     jboolean needsInit;
   * If true, the surface requires some one-time initialization, which should
   * be performed after a context has been made current to the surface for
   * the first time.
   *
   *     jint x/yOffset
   * The offset in pixels of the OpenGL viewport origin from the lower-left
   * corner of the heavyweight drawable.  For example, a top-level frame on
   * Windows XP has lower-left insets of (4,4).  The OpenGL viewport origin
   * would typically begin at the lower-left corner of the client region (inside
   * the frame decorations), but AWT/Swing will take the insets into account
   * when rendering into that window.  So in order to account for this, we
   * need to adjust the OpenGL viewport origin by an x/yOffset of (-4,-4).  On
   * X11, top-level frames typically don't have this insets issue, so their
   * x/yOffset would be (0,0) (the same applies to pbuffers).
   *
   *     jint width/height;
   * The cached surface bounds.  For offscreen surface types (OGLSD_FBOBJECT,
   * OGLSD_TEXTURE, etc.) these values must remain constant.  Onscreen window
   * surfaces (OGLSD_WINDOW, OGLSD_FLIP_BACKBUFFER, etc.) may have their
   * bounds changed in response to a programmatic or user-initiated event, so
   * these values represent the last known dimensions.  To determine the true
   * current bounds of this surface, query the native Drawable through the
   * privOps field.
   *
   *     GLuint textureID;
   * The texture object handle, as generated by glGenTextures().  If this value
   * is zero, the texture has not yet been initialized.
   *
   *     jint textureWidth/Height;
   * The actual bounds of the texture object for this surface.  If the
   * GL_ARB_texture_non_power_of_two extension is not present, the dimensions
   * of an OpenGL texture object must be a power-of-two (e.g. 64x32 or 128x512).
   * The texture image that we care about has dimensions specified by the width
   * and height fields in this OGLSDOps structure.  For example, if the image
   * to be stored in the texture has dimensions 115x47, the actual OpenGL
   * texture we allocate will have dimensions 128x64 to meet the pow2
   * restriction.  The image bounds within the texture can be accessed using
   * floating point texture coordinates in the range [0.0,1.0].
   *
   *     GLenum textureTarget;
   * The texture target of the texture object for this surface.  If this
   * surface is not backed by a texture, this value is set to zero.  Otherwise,
   * this value is GL_TEXTURE_RECTANGLE_ARB when the GL_ARB_texture_rectangle
   * extension is in use; if not, it is set to GL_TEXTURE_2D.
   *
   *     GLint textureFilter;
   * The current filter state for this texture object (can be either GL_NEAREST
   * or GL_LINEAR).  We cache this value here and check it before updating
   * the filter state to avoid redundant calls to glTexParameteri() when the
   * filter state remains constant (see the OGLSD_UPDATE_TEXTURE_FILTER()
   * macro below).
   *
   *     GLuint fbobjectID, depthID;
   * The object handles for the framebuffer object and depth renderbuffer
   * associated with this surface.  These fields are only used when
   * drawableType is OGLSD_FBOBJECT, otherwise they are zero.
   */
  struct _OGLSDOps {
      SurfaceDataOps               sdOps;
      void                         *privOps;
      jobject                      graphicsConfig;
      jint                         drawableType;
      GLenum                       activeBuffer;
      jboolean                     isOpaque;
      jboolean                     needsInit;
      jint                         xOffset;
      jint                         yOffset;
      jint                         width;
      jint                         height;
      GLuint                       textureID;
      jint                         textureWidth;
      jint                         textureHeight;
      GLenum                       textureTarget;
      GLint                        textureFilter;
      GLuint                       fbobjectID;
      GLuint                       depthID;
  };
  
  /**
   * The following convenience macros are used when rendering rectangles (either
   * a single rectangle, or a whole series of them).  To render a single
   * rectangle, simply invoke the GLRECT() macro.  To render a whole series of
   * rectangles, such as spans in a complex shape, first invoke GLRECT_BEGIN(),
   * then invoke the appropriate inner loop macro (either XYXY or XYWH) for
   * each rectangle, and finally invoke GLRECT_END() to notify OpenGL that the
   * vertex list is complete.  Care should be taken to avoid calling OpenGL
   * commands (besides GLRECT_BODY_*()) inside the BEGIN/END pair.
   */
  
  #define GLRECT_BEGIN j2d_glBegin(GL_QUADS)
  
  #define GLRECT_BODY_XYXY(x1, y1, x2, y2) \
      do { \
          j2d_glVertex2i(x1, y1); \
          j2d_glVertex2i(x2, y1); \
          j2d_glVertex2i(x2, y2); \
          j2d_glVertex2i(x1, y2); \
      } while (0)
  
  #define GLRECT_BODY_XYWH(x, y, w, h) \
      GLRECT_BODY_XYXY(x, y, (x) + (w), (y) + (h))
  
  #define GLRECT_END j2d_glEnd()
  
  #define GLRECT(x, y, w, h) \
      do { \
          GLRECT_BEGIN; \
          GLRECT_BODY_XYWH(x, y, w, h); \
          GLRECT_END; \
      } while (0)
  
  /**
   * These are shorthand names for the surface type constants defined in
   * OGLSurfaceData.java.
   */
  #define OGLSD_UNDEFINED       sun_java2d_pipe_hw_AccelSurface_UNDEFINED
  #define OGLSD_WINDOW          sun_java2d_pipe_hw_AccelSurface_WINDOW
  #define OGLSD_TEXTURE         sun_java2d_pipe_hw_AccelSurface_TEXTURE
  #define OGLSD_FLIP_BACKBUFFER sun_java2d_pipe_hw_AccelSurface_FLIP_BACKBUFFER
  #define OGLSD_FBOBJECT        sun_java2d_pipe_hw_AccelSurface_RT_TEXTURE
  
  /**
   * These are shorthand names for the filtering method constants used by
   * image transform methods.
   */
  #define OGLSD_XFORM_DEFAULT 0
  #define OGLSD_XFORM_NEAREST_NEIGHBOR \
      java_awt_image_AffineTransformOp_TYPE_NEAREST_NEIGHBOR
  #define OGLSD_XFORM_BILINEAR \
      java_awt_image_AffineTransformOp_TYPE_BILINEAR
  
  /**
   * Helper macros that update the current texture filter state only when
   * it needs to be changed, which helps reduce overhead for small texturing
   * operations.  The filter state is set on a per-texture (not per-context)
   * basis; for example, it is possible for one texture to be using GL_NEAREST
   * while another texture uses GL_LINEAR under the same context.
   */
  #define OGLSD_INIT_TEXTURE_FILTER(oglSDOps, filter)                          \
      do {                                                                     \
          j2d_glTexParameteri((oglSDOps)->textureTarget,                       \
                              GL_TEXTURE_MAG_FILTER, (filter));                \
          j2d_glTexParameteri((oglSDOps)->textureTarget,                       \
                              GL_TEXTURE_MIN_FILTER, (filter));                \
          (oglSDOps)->textureFilter = (filter);                                \
      } while (0)
  
  #define OGLSD_UPDATE_TEXTURE_FILTER(oglSDOps, filter)    \
      do {                                                 \
          if ((oglSDOps)->textureFilter != (filter)) {     \
              OGLSD_INIT_TEXTURE_FILTER(oglSDOps, filter); \
          }                                                \
      } while (0)
  
  /**
   * Convenience macros for setting the texture wrap mode for a given target.
   * The texture wrap mode should be reset to our default value of
   * GL_CLAMP_TO_EDGE by calling OGLSD_RESET_TEXTURE_WRAP() when a texture
   * is first created.  If another mode is needed (e.g. GL_REPEAT in the case
   * of TexturePaint acceleration), one can call the OGLSD_UPDATE_TEXTURE_WRAP()
   * macro to easily set up the new wrap mode.  However, it is important to
   * restore the wrap mode back to its default value (by calling the
   * OGLSD_RESET_TEXTURE_WRAP() macro) when the operation is finished.
   */
  #define OGLSD_UPDATE_TEXTURE_WRAP(target, wrap)                   \
      do {                                                          \
          j2d_glTexParameteri((target), GL_TEXTURE_WRAP_S, (wrap)); \
          j2d_glTexParameteri((target), GL_TEXTURE_WRAP_T, (wrap)); \
      } while (0)
  
  #define OGLSD_RESET_TEXTURE_WRAP(target) \
      OGLSD_UPDATE_TEXTURE_WRAP(target, GL_CLAMP_TO_EDGE)
  
  /**
   * Exported methods.
   */
  jint OGLSD_Lock(JNIEnv *env,
                  SurfaceDataOps *ops, SurfaceDataRasInfo *pRasInfo,
                  jint lockflags);
  void OGLSD_GetRasInfo(JNIEnv *env,
                        SurfaceDataOps *ops, SurfaceDataRasInfo *pRasInfo);
  void OGLSD_Unlock(JNIEnv *env,
                    SurfaceDataOps *ops, SurfaceDataRasInfo *pRasInfo);
  void OGLSD_Dispose(JNIEnv *env, SurfaceDataOps *ops);
  void OGLSD_Delete(JNIEnv *env, OGLSDOps *oglsdo);
  jint OGLSD_NextPowerOfTwo(jint val, jint max);
  jboolean OGLSD_InitFBObject(GLuint *fbobjectID, GLuint *depthID,
                              GLuint textureID, GLenum textureTarget,
                              jint textureWidth, jint textureHeight);
  
  #endif /* OGLSurfaceData_h_Included */
  