Git conversion: Make reactos the root directory, move rosapps, rostests, wallpapers into modules, and delete rossubsys.

dll/opengl/mesa/main/buffers.c

@@ -0,0 +1,347 @@
+/*
+ * Mesa 3-D graphics library
+ * Version:  7.1
+ *
+ * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/**
+ * \file buffers.c
+ * glReadBuffer, DrawBuffer functions.
+ */
+
+#include <precomp.h>
+
+#define BAD_MASK ~0u
+
+/**
+ * Return bitmask of BUFFER_BIT_* flags indicating which color buffers are
+ * available to the rendering context (for drawing or reading).
+ * This depends on the type of framebuffer.  For window system framebuffers
+ * we look at the framebuffer's visual.  But for user-create framebuffers we
+ * look at the number of supported color attachments.
+ * \param fb  the framebuffer to draw to, or read from
+ * \return  bitmask of BUFFER_BIT_* flags
+ */
+static GLbitfield
+supported_buffer_bitmask(const struct gl_context *ctx, const struct gl_framebuffer *fb)
+{
+   GLbitfield mask = 0x0;
+
+   /* A window system framebuffer */
+   GLint i;
+   mask = BUFFER_BIT_FRONT_LEFT; /* always have this */
+   if (fb->Visual.stereoMode) {
+      mask |= BUFFER_BIT_FRONT_RIGHT;
+      if (fb->Visual.doubleBufferMode) {
+         mask |= BUFFER_BIT_BACK_LEFT | BUFFER_BIT_BACK_RIGHT;
+      }
+   }
+   else if (fb->Visual.doubleBufferMode) {
+      mask |= BUFFER_BIT_BACK_LEFT;
+   }
+
+   for (i = 0; i < fb->Visual.numAuxBuffers; i++) {
+      mask |= (BUFFER_BIT_AUX0 << i);
+   }
+
+   return mask;
+}
+
+
+/**
+ * Helper routine used by glDrawBuffer and glDrawBuffersARB.
+ * Given a GLenum naming one or more color buffers (such as
+ * GL_FRONT_AND_BACK), return the corresponding bitmask of BUFFER_BIT_* flags.
+ */
+static GLbitfield
+draw_buffer_enum_to_bitmask(GLenum buffer)
+{
+   switch (buffer) {
+      case GL_NONE:
+         return 0;
+      case GL_FRONT:
+         return BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_FRONT_RIGHT;
+      case GL_BACK:
+         return BUFFER_BIT_BACK_LEFT | BUFFER_BIT_BACK_RIGHT;
+      case GL_RIGHT:
+         return BUFFER_BIT_FRONT_RIGHT | BUFFER_BIT_BACK_RIGHT;
+      case GL_FRONT_RIGHT:
+         return BUFFER_BIT_FRONT_RIGHT;
+      case GL_BACK_RIGHT:
+         return BUFFER_BIT_BACK_RIGHT;
+      case GL_BACK_LEFT:
+         return BUFFER_BIT_BACK_LEFT;
+      case GL_FRONT_AND_BACK:
+         return BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_BACK_LEFT
+              | BUFFER_BIT_FRONT_RIGHT | BUFFER_BIT_BACK_RIGHT;
+      case GL_LEFT:
+         return BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_BACK_LEFT;
+      case GL_FRONT_LEFT:
+         return BUFFER_BIT_FRONT_LEFT;
+      case GL_AUX0:
+         return BUFFER_BIT_AUX0;
+      case GL_AUX1:
+      case GL_AUX2:
+      case GL_AUX3:
+         return 1 << BUFFER_COUNT; /* invalid, but not BAD_MASK */
+      default:
+         /* error */
+         return BAD_MASK;
+   }
+}
+
+
+/**
+ * Helper routine used by glReadBuffer.
+ * Given a GLenum naming a color buffer, return the index of the corresponding
+ * renderbuffer (a BUFFER_* value).
+ * return -1 for an invalid buffer.
+ */
+static GLint
+read_buffer_enum_to_index(GLenum buffer)
+{
+   switch (buffer) {
+      case GL_FRONT:
+         return BUFFER_FRONT_LEFT;
+      case GL_BACK:
+         return BUFFER_BACK_LEFT;
+      case GL_RIGHT:
+         return BUFFER_FRONT_RIGHT;
+      case GL_FRONT_RIGHT:
+         return BUFFER_FRONT_RIGHT;
+      case GL_BACK_RIGHT:
+         return BUFFER_BACK_RIGHT;
+      case GL_BACK_LEFT:
+         return BUFFER_BACK_LEFT;
+      case GL_LEFT:
+         return BUFFER_FRONT_LEFT;
+      case GL_FRONT_LEFT:
+         return BUFFER_FRONT_LEFT;
+      case GL_AUX0:
+         return BUFFER_AUX0;
+      case GL_AUX1:
+      case GL_AUX2:
+      case GL_AUX3:
+         return BUFFER_COUNT; /* invalid, but not -1 */
+      default:
+         /* error */
+         return -1;
+   }
+}
+
+
+/**
+ * Called by glDrawBuffer().
+ * Specify which renderbuffer(s) to draw into for the first color output.
+ * <buffer> can name zero, one, two or four renderbuffers!
+ * \sa _mesa_DrawBuffersARB
+ *
+ * \param buffer  buffer token such as GL_LEFT or GL_FRONT_AND_BACK, etc.
+ *
+ * Note that the behaviour of this function depends on whether the
+ * current ctx->DrawBuffer is a window-system framebuffer (Name=0) or
+ * a user-created framebuffer object (Name!=0).
+ *   In the former case, we update the per-context ctx->Color.DrawBuffer
+ *   state var _and_ the FB's ColorDrawBuffer state.
+ *   In the later case, we update the FB's ColorDrawBuffer state only.
+ *
+ * Furthermore, upon a MakeCurrent() or BindFramebuffer() call, if the
+ * new FB is a window system FB, we need to re-update the FB's
+ * ColorDrawBuffer state to match the context.  This is handled in
+ * _mesa_update_framebuffer().
+ *
+ * See the GL_EXT_framebuffer_object spec for more info.
+ */
+void GLAPIENTRY
+_mesa_DrawBuffer(GLenum buffer)
+{
+   GLbitfield destMask;
+   GET_CURRENT_CONTEXT(ctx);
+   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); /* too complex... */
+
+   if (MESA_VERBOSE & VERBOSE_API) {
+      _mesa_debug(ctx, "glDrawBuffer %s\n", _mesa_lookup_enum_by_nr(buffer));
+   }
+
+   if (buffer == GL_NONE) {
+      destMask = 0x0;
+   }
+   else {
+      const GLbitfield supportedMask
+         = supported_buffer_bitmask(ctx, ctx->DrawBuffer);
+      destMask = draw_buffer_enum_to_bitmask(buffer);
+      if (destMask == BAD_MASK) {
+         /* totally bogus buffer */
+         _mesa_error(ctx, GL_INVALID_ENUM, "glDrawBuffer(buffer=0x%x)", buffer);
+         return;
+      }
+      destMask &= supportedMask;
+      if (destMask == 0x0) {
+         /* none of the named color buffers exist! */
+         _mesa_error(ctx, GL_INVALID_OPERATION,
+                     "glDrawBuffer(buffer=0x%x)", buffer);
+         return;
+      }
+   }
+
+   /* if we get here, there's no error so set new state */
+   _mesa_drawbuffer(ctx, buffer, destMask);
+
+   /*
+    * Call device driver function.
+    */
+   if (ctx->Driver.DrawBuffer)
+      ctx->Driver.DrawBuffer(ctx, buffer);
+}
+
+/**
+ * Performs necessary state updates when _mesa_drawbuffers makes an
+ * actual change.
+ */
+static void
+updated_drawbuffers(struct gl_context *ctx)
+{
+   FLUSH_VERTICES(ctx, _NEW_BUFFERS);
+}
+
+/**
+ * Helper function to set the GL_DRAW_BUFFER state in the context and
+ * current FBO.  Called via glDrawBuffer(), glDrawBuffersARB()
+ *
+ * All error checking will have been done prior to calling this function
+ * so nothing should go wrong at this point.
+ *
+ * \param ctx  current context
+ * \param n    number of color outputs to set
+ * \param buffers  array[n] of colorbuffer names, like GL_LEFT.
+ * \param destMask  array[n] of BUFFER_BIT_* bitmasks which correspond to the
+ *                  colorbuffer names.  (i.e. GL_FRONT_AND_BACK =>
+ *                  BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_BACK_LEFT).
+ */
+void
+_mesa_drawbuffer(struct gl_context *ctx, const GLenum buffers, GLbitfield destMask)
+{
+   struct gl_framebuffer *fb = ctx->DrawBuffer;
+   GLint bufIndex;
+
+   if (!destMask) {
+      /* compute destMask values now */
+      const GLbitfield supportedMask = supported_buffer_bitmask(ctx, fb);
+      destMask = draw_buffer_enum_to_bitmask(buffers);
+      ASSERT(destmask != BAD_MASK);
+      destMask &= supportedMask;
+   }
+   
+   bufIndex = _mesa_ffs(destMask) - 1;
+
+   if (fb->_ColorDrawBufferIndex != bufIndex) {
+      updated_drawbuffers(ctx);
+      fb->_ColorDrawBufferIndex = bufIndex;
+   }
+   fb->ColorDrawBuffer = buffers;
+
+   if (ctx->Color.DrawBuffer != fb->ColorDrawBuffer) {
+      updated_drawbuffers(ctx);
+      ctx->Color.DrawBuffer = fb->ColorDrawBuffer;
+   }
+}
+
+
+/**
+ * Update the current drawbuffer's _ColorDrawBufferIndex[] list, etc.
+ * from the context's Color.DrawBuffer[] state.
+ * Use when changing contexts.
+ */
+void
+_mesa_update_draw_buffer(struct gl_context *ctx)
+{
+   _mesa_drawbuffer(ctx, ctx->Color.DrawBuffer, 0);
+}
+
+
+/**
+ * Like \sa _mesa_drawbuffers(), this is a helper function for setting
+ * GL_READ_BUFFER state in the context and current FBO.
+ * \param ctx  the rendering context
+ * \param buffer  GL_FRONT, GL_BACK, GL_COLOR_ATTACHMENT0, etc.
+ * \param bufferIndex  the numerical index corresponding to 'buffer'
+ */
+void
+_mesa_readbuffer(struct gl_context *ctx, GLenum buffer, GLint bufferIndex)
+{
+   struct gl_framebuffer *fb = ctx->ReadBuffer;
+
+   ctx->Pixel.ReadBuffer = buffer;
+
+   fb->ColorReadBuffer = buffer;
+   fb->_ColorReadBufferIndex = bufferIndex;
+
+   ctx->NewState |= _NEW_BUFFERS;
+}
+
+
+
+/**
+ * Called by glReadBuffer to set the source renderbuffer for reading pixels.
+ * \param mode color buffer such as GL_FRONT, GL_BACK, etc.
+ */
+void GLAPIENTRY
+_mesa_ReadBuffer(GLenum buffer)
+{
+   struct gl_framebuffer *fb;
+   GLbitfield supportedMask;
+   GLint srcBuffer;
+   GET_CURRENT_CONTEXT(ctx);
+   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
+
+   if (MESA_VERBOSE & VERBOSE_API)
+      _mesa_debug(ctx, "glReadBuffer %s\n", _mesa_lookup_enum_by_nr(buffer));
+
+   fb = ctx->ReadBuffer;
+
+   if (MESA_VERBOSE & VERBOSE_API)
+      _mesa_debug(ctx, "glReadBuffer %s\n", _mesa_lookup_enum_by_nr(buffer));
+
+   /* general case / window-system framebuffer */
+   srcBuffer = read_buffer_enum_to_index(buffer);
+   if (srcBuffer == -1) {
+      _mesa_error(ctx, GL_INVALID_ENUM,
+                  "glReadBuffer(buffer=0x%x)", buffer);
+      return;
+   }
+   supportedMask = supported_buffer_bitmask(ctx, fb);
+   if (((1 << srcBuffer) & supportedMask) == 0) {
+      _mesa_error(ctx, GL_INVALID_OPERATION,
+                  "glReadBuffer(buffer=0x%x)", buffer);
+      return;
+   }
+
+   /* OK, all error checking has been completed now */
+
+   _mesa_readbuffer(ctx, buffer, srcBuffer);
+   ctx->NewState |= _NEW_BUFFERS;
+
+   /*
+    * Call device driver function.
+    */
+   if (ctx->Driver.ReadBuffer)
+      (*ctx->Driver.ReadBuffer)(ctx, buffer);
+}