Initial import.

1 files changed, 332 insertions, 0 deletions

diff --git a/src/mesa/swrast/s_alphabuf.c b/src/mesa/swrast/s_alphabuf.c
new file mode 100644
index 0000000..f57449c
--- /dev/null
+++ b/src/mesa/swrast/s_alphabuf.c
@@ -0,0 +1,332 @@
+/*
+ * Mesa 3-D graphics library
+ * Version:  6.1
+ *
+ * Copyright (C) 1999-2004  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.
+ */
+
+
+/*
+ * Software alpha planes.  Many frame buffers don't have alpha bits so
+ * we simulate them in software.
+ */
+
+
+#include "glheader.h"
+#include "colormac.h"
+#include "context.h"
+#include "imports.h"
+
+#include "s_context.h"
+#include "s_alphabuf.h"
+
+
+/*
+ * Allocate a new front and back alpha buffer.
+ */
+void
+_swrast_alloc_alpha_buffers( GLframebuffer *buffer )
+{
+   const GLint bytes = buffer->Width * buffer->Height * sizeof(GLchan);
+
+   ASSERT(buffer->UseSoftwareAlphaBuffers);
+
+   if (buffer->FrontLeftAlpha) {
+      MESA_PBUFFER_FREE( buffer->FrontLeftAlpha );
+   }
+   buffer->FrontLeftAlpha = (GLchan *) MESA_PBUFFER_ALLOC( bytes );
+   if (!buffer->FrontLeftAlpha) {
+      /* out of memory */
+      _mesa_error( NULL, GL_OUT_OF_MEMORY,
+                   "Couldn't allocate front-left alpha buffer" );
+   }
+
+   if (buffer->Visual.doubleBufferMode) {
+      if (buffer->BackLeftAlpha) {
+         MESA_PBUFFER_FREE( buffer->BackLeftAlpha );
+      }
+      buffer->BackLeftAlpha = (GLchan *) MESA_PBUFFER_ALLOC( bytes );
+      if (!buffer->BackLeftAlpha) {
+         /* out of memory */
+         _mesa_error( NULL, GL_OUT_OF_MEMORY,
+                      "Couldn't allocate back-left alpha buffer" );
+      }
+   }
+
+   if (buffer->Visual.stereoMode) {
+      if (buffer->FrontRightAlpha) {
+         MESA_PBUFFER_FREE( buffer->FrontRightAlpha );
+      }
+      buffer->FrontRightAlpha = (GLchan *) MESA_PBUFFER_ALLOC( bytes );
+      if (!buffer->FrontRightAlpha) {
+         /* out of memory */
+         _mesa_error( NULL, GL_OUT_OF_MEMORY,
+                      "Couldn't allocate front-right alpha buffer" );
+      }
+
+      if (buffer->Visual.doubleBufferMode) {
+         if (buffer->BackRightAlpha) {
+            MESA_PBUFFER_FREE( buffer->BackRightAlpha );
+         }
+         buffer->BackRightAlpha = (GLchan *) MESA_PBUFFER_ALLOC( bytes );
+         if (!buffer->BackRightAlpha) {
+            /* out of memory */
+            _mesa_error( NULL, GL_OUT_OF_MEMORY,
+                         "Couldn't allocate back-right alpha buffer" );
+         }
+      }
+   }
+}
+
+
+/*
+ * Clear all the alpha buffers
+ */
+void
+_swrast_clear_alpha_buffers( GLcontext *ctx )
+{
+   GLchan aclear;
+   GLuint bufferBit;
+
+   CLAMPED_FLOAT_TO_CHAN(aclear, ctx->Color.ClearColor[3]);
+
+   ASSERT(ctx->DrawBuffer->UseSoftwareAlphaBuffers);
+   ASSERT(ctx->Color.ColorMask[ACOMP]);
+
+   /* loop over four possible alpha buffers */
+   for (bufferBit = 1; bufferBit <= 8; bufferBit = bufferBit << 1) {
+      if (bufferBit & ctx->Color._DrawDestMask) {
+         GLchan *buffer;
+         if (bufferBit == DD_FRONT_LEFT_BIT) {
+            buffer = ctx->DrawBuffer->FrontLeftAlpha;
+         }
+         else if (bufferBit == DD_FRONT_RIGHT_BIT) {
+            buffer = ctx->DrawBuffer->FrontRightAlpha;
+         }
+         else if (bufferBit == DD_BACK_LEFT_BIT) {
+            buffer = ctx->DrawBuffer->BackLeftAlpha;
+         }
+         else {
+            buffer = ctx->DrawBuffer->BackRightAlpha;
+         }
+
+         if (ctx->Scissor.Enabled) {
+            /* clear scissor region */
+            GLint j;
+            GLint rowLen = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
+            GLint rows = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
+            GLint width = ctx->DrawBuffer->Width;
+            GLchan *aptr = buffer
+                          + ctx->DrawBuffer->_Ymin * ctx->DrawBuffer->Width
+                          + ctx->DrawBuffer->_Xmin;
+            for (j = 0; j < rows; j++) {
+#if CHAN_BITS == 8
+               MEMSET( aptr, aclear, rowLen );
+#elif CHAN_BITS == 16
+               MEMSET16( aptr, aclear, rowLen );
+#else
+               GLint i;
+               for (i = 0; i < rowLen; i++) {
+                  aptr[i] = aclear;
+               }
+#endif
+               aptr += width;
+            }
+         }
+         else {
+            /* clear whole buffer */
+            GLuint pixels = ctx->DrawBuffer->Width * ctx->DrawBuffer->Height;
+#if CHAN_BITS == 8
+            MEMSET(buffer, aclear, pixels);
+#elif CHAN_BITS == 16
+            MEMSET16(buffer, aclear, pixels);
+#else
+            GLuint i;
+            for (i = 0; i < pixels; i++) {
+               buffer[i] = aclear;
+            }
+#endif
+         }
+      }
+   }
+}
+
+
+
+static INLINE
+GLchan *get_alpha_buffer( GLcontext *ctx )
+{
+   SWcontext *swrast = SWRAST_CONTEXT(ctx);
+
+   switch (swrast->CurrentBufferBit) {
+   case DD_FRONT_LEFT_BIT:
+      return ctx->DrawBuffer->FrontLeftAlpha;
+   case DD_BACK_LEFT_BIT:
+      return ctx->DrawBuffer->BackLeftAlpha;
+   case DD_FRONT_RIGHT_BIT:
+      return ctx->DrawBuffer->FrontRightAlpha;
+   case DD_BACK_RIGHT_BIT:
+      return ctx->DrawBuffer->BackRightAlpha;
+   default:
+      _mesa_problem(ctx, "Bad CurrentBuffer in get_alpha_buffer()");
+      return (GLchan *) ctx->DrawBuffer->FrontLeftAlpha;
+   }
+}
+
+
+void
+_swrast_write_alpha_span( GLcontext *ctx, GLuint n, GLint x, GLint y,
+                        CONST GLchan rgba[][4], const GLubyte mask[] )
+{
+   GLchan *buffer, *aptr;
+   GLuint i;
+
+   buffer = get_alpha_buffer(ctx);
+   aptr = buffer + y * ctx->DrawBuffer->Width + x;
+
+   if (mask) {
+      for (i=0;i<n;i++) {
+         if (mask[i]) {
+            *aptr = rgba[i][ACOMP];
+         }
+         aptr++;
+      }
+   }
+   else {
+      for (i=0;i<n;i++) {
+         *aptr++ = rgba[i][ACOMP];
+      }
+   }
+}
+
+
+void
+_swrast_write_mono_alpha_span( GLcontext *ctx, GLuint n, GLint x, GLint y,
+                             GLchan alpha, const GLubyte mask[] )
+{
+   GLchan *buffer, *aptr;
+   GLuint i;
+
+   buffer = get_alpha_buffer(ctx);
+   aptr = buffer + y * ctx->DrawBuffer->Width + x;
+
+   if (mask) {
+      for (i=0;i<n;i++) {
+         if (mask[i]) {
+            *aptr = alpha;
+         }
+         aptr++;
+      }
+   }
+   else {
+      for (i=0;i<n;i++) {
+         *aptr++ = alpha;
+      }
+   }
+}
+
+
+void
+_swrast_write_alpha_pixels( GLcontext *ctx,
+                          GLuint n, const GLint x[], const GLint y[],
+                          CONST GLchan rgba[][4], const GLubyte mask[] )
+{
+   GLchan *buffer;
+   GLuint i;
+
+   buffer = get_alpha_buffer(ctx);
+
+   if (mask) {
+      for (i=0;i<n;i++) {
+         if (mask[i]) {
+            GLchan *aptr = buffer + y[i] * ctx->DrawBuffer->Width + x[i];
+            *aptr = rgba[i][ACOMP];
+         }
+      }
+   }
+   else {
+      for (i=0;i<n;i++) {
+         GLchan *aptr = buffer + y[i] * ctx->DrawBuffer->Width + x[i];
+         *aptr = rgba[i][ACOMP];
+      }
+   }
+}
+
+
+void
+_swrast_write_mono_alpha_pixels( GLcontext *ctx,
+                               GLuint n, const GLint x[], const GLint y[],
+                               GLchan alpha, const GLubyte mask[] )
+{
+   GLchan *buffer;
+   GLuint i;
+
+   buffer = get_alpha_buffer(ctx);
+
+   if (mask) {
+      for (i=0;i<n;i++) {
+         if (mask[i]) {
+            GLchan *aptr = buffer + y[i] * ctx->DrawBuffer->Width + x[i];
+            *aptr = alpha;
+         }
+      }
+   }
+   else {
+      for (i=0;i<n;i++) {
+         GLchan *aptr = buffer + y[i] * ctx->DrawBuffer->Width + x[i];
+         *aptr = alpha;
+      }
+   }
+}
+
+
+
+void
+_swrast_read_alpha_span( GLcontext *ctx,
+                       GLuint n, GLint x, GLint y, GLchan rgba[][4] )
+{
+   const GLchan *buffer, *aptr;
+   GLuint i;
+
+   buffer = get_alpha_buffer(ctx);
+   aptr = buffer + y * ctx->DrawBuffer->Width + x;
+
+   for (i = 0; i < n; i++)
+      rgba[i][ACOMP] = *aptr++;
+}
+
+
+void
+_swrast_read_alpha_pixels( GLcontext *ctx,
+                         GLuint n, const GLint x[], const GLint y[],
+                         GLchan rgba[][4], const GLubyte mask[] )
+{
+   const GLchan *buffer;
+   GLuint i;
+
+   buffer = get_alpha_buffer(ctx);
+
+   for (i = 0; i < n; i++) {
+      if (mask[i]) {
+         const GLchan *aptr = buffer + y[i] * ctx->DrawBuffer->Width + x[i];
+         rgba[i][ACOMP] = *aptr;
+      }
+   }
+}