Initial import.

1 files changed, 321 insertions, 0 deletions

diff --git a/src/mesa/swrast/s_buffers.c b/src/mesa/swrast/s_buffers.c
new file mode 100644
index 0000000..26b4f90
--- /dev/null
+++ b/src/mesa/swrast/s_buffers.c
@@ -0,0 +1,321 @@
+/*
+ * 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.
+ */
+
+
+#include "glheader.h"
+#include "colormac.h"
+#include "macros.h"
+#include "imports.h"
+
+#include "s_accum.h"
+#include "s_alphabuf.h"
+#include "s_auxbuffer.h"
+#include "s_context.h"
+#include "s_depth.h"
+#include "s_masking.h"
+#include "s_stencil.h"
+
+
+/**
+ * Clear the color buffer when glColorMask or glIndexMask is in effect.
+ * We'll have specified which color buffer to clear by previously
+ * calling Driver.SetBuffer().
+ */
+static void
+clear_color_buffer_with_masking( GLcontext *ctx )
+{
+   SWcontext *swrast = SWRAST_CONTEXT(ctx);
+   const GLint x = ctx->DrawBuffer->_Xmin;
+   const GLint y = ctx->DrawBuffer->_Ymin;
+   const GLint height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
+   const GLint width  = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
+
+   if (ctx->Visual.rgbMode) {
+      /* RGBA mode */
+      GLchan clearColor[4];
+      GLint i;
+      CLAMPED_FLOAT_TO_CHAN(clearColor[RCOMP], ctx->Color.ClearColor[0]);
+      CLAMPED_FLOAT_TO_CHAN(clearColor[GCOMP], ctx->Color.ClearColor[1]);
+      CLAMPED_FLOAT_TO_CHAN(clearColor[BCOMP], ctx->Color.ClearColor[2]);
+      CLAMPED_FLOAT_TO_CHAN(clearColor[ACOMP], ctx->Color.ClearColor[3]);
+      for (i = 0; i < height; i++) {
+         GLchan rgba[MAX_WIDTH][4];
+         GLint j;
+         for (j = 0; j < width; j++) {
+            COPY_CHAN4(rgba[j], clearColor);
+         }
+         _swrast_mask_rgba_array( ctx, width, x, y + i, rgba );
+         (*swrast->Driver.WriteRGBASpan)( ctx, width, x, y + i,
+                                          (CONST GLchan (*)[4]) rgba, NULL );
+      }
+   }
+   else {
+      /* Color index mode */
+      GLuint span[MAX_WIDTH];
+      GLubyte mask[MAX_WIDTH];
+      GLint i, j;
+      MEMSET( mask, 1, width );
+      for (i=0;i<height;i++) {
+         for (j=0;j<width;j++) {
+            span[j] = ctx->Color.ClearIndex;
+         }
+         _swrast_mask_index_array( ctx, width, x, y + i, span );
+         (*swrast->Driver.WriteCI32Span)( ctx, width, x, y + i, span, mask );
+      }
+   }
+}
+
+
+/**
+ * Clear a color buffer without index/channel masking.
+ * We'll have specified which color buffer to clear by previously
+ * calling Driver.SetBuffer().
+ */
+static void
+clear_color_buffer(GLcontext *ctx)
+{
+   SWcontext *swrast = SWRAST_CONTEXT(ctx);
+   const GLint x = ctx->DrawBuffer->_Xmin;
+   const GLint y = ctx->DrawBuffer->_Ymin;
+   const GLint height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
+   const GLint width  = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
+
+   if (ctx->Visual.rgbMode) {
+      /* RGBA mode */
+      GLchan clearColor[4];
+      GLint i;
+
+      CLAMPED_FLOAT_TO_CHAN(clearColor[RCOMP], ctx->Color.ClearColor[0]);
+      CLAMPED_FLOAT_TO_CHAN(clearColor[GCOMP], ctx->Color.ClearColor[1]);
+      CLAMPED_FLOAT_TO_CHAN(clearColor[BCOMP], ctx->Color.ClearColor[2]);
+      CLAMPED_FLOAT_TO_CHAN(clearColor[ACOMP], ctx->Color.ClearColor[3]);
+
+      ASSERT(*((GLuint *) &ctx->Color.ColorMask) == 0xffffffff);
+      ASSERT(swrast->Driver.WriteRGBASpan);
+
+      for (i = 0; i < height; i++) {
+         (*swrast->Driver.WriteMonoRGBASpan)( ctx, width, x, y + i,
+                                              clearColor, NULL );
+      }
+   }
+   else {
+      /* Color index mode */
+      GLint i;
+      ASSERT((ctx->Color.IndexMask & ((1 << ctx->Visual.indexBits) - 1))
+             == (GLuint) ((1 << ctx->Visual.indexBits) - 1));
+      ASSERT(swrast->Driver.WriteMonoCISpan);
+      for (i = 0; i < height; i++) {
+         (*swrast->Driver.WriteMonoCISpan)( ctx, width, x, y + i,
+                                            ctx->Color.ClearIndex, NULL);
+      }
+   }
+}
+
+
+/**
+ * Clear the front/back/left/right/aux color buffers.
+ * This function is usually only called if the device driver can't
+ * clear its own color buffers for some reason (such as with masking).
+ */
+static void
+clear_color_buffers(GLcontext *ctx)
+{
+   SWcontext *swrast = SWRAST_CONTEXT(ctx);
+   const GLuint colorMask = *((GLuint *) &ctx->Color.ColorMask);
+   GLuint bufferBit;
+
+   /* loop over four possible dest color buffers */
+   for (bufferBit = 1; bufferBit <= DD_AUX3_BIT; bufferBit <<= 1) {
+      if (bufferBit & ctx->Color._DrawDestMask) {
+         (*swrast->Driver.SetBuffer)(ctx, ctx->DrawBuffer, bufferBit);
+
+         if (colorMask != 0xffffffff) {
+            clear_color_buffer_with_masking(ctx);
+         }
+         else {
+            clear_color_buffer(ctx);
+         }
+      }
+   }
+
+   /* restore default read/draw buffer */
+   _swrast_use_draw_buffer(ctx);
+}
+
+
+/**
+ * Called via the device driver's ctx->Driver.Clear() function if the
+ * device driver can't clear one or more of the buffers itself.
+ * \param mask  bitwise-OR of DD_*_BIT flags.
+ * \param all  if GL_TRUE, clear whole buffer, else clear specified region.
+ */
+void
+_swrast_Clear( GLcontext *ctx, GLbitfield mask,
+	       GLboolean all,
+	       GLint x, GLint y, GLint width, GLint height )
+{
+   SWcontext *swrast = SWRAST_CONTEXT(ctx);
+   (void) all; (void) x; (void) y; (void) width; (void) height;
+#ifdef DEBUG
+   {
+      const GLbitfield legalBits =
+         DD_FRONT_LEFT_BIT |
+	 DD_FRONT_RIGHT_BIT |
+	 DD_BACK_LEFT_BIT |
+	 DD_BACK_RIGHT_BIT |
+	 DD_DEPTH_BIT |
+	 DD_STENCIL_BIT |
+	 DD_ACCUM_BIT |
+         DD_AUX0_BIT |
+         DD_AUX1_BIT |
+         DD_AUX2_BIT |
+         DD_AUX3_BIT;
+      assert((mask & (~legalBits)) == 0);
+   }
+#endif
+
+   RENDER_START(swrast,ctx);
+
+   /* do software clearing here */
+   if (mask) {
+      if (mask & ctx->Color._DrawDestMask) {
+         clear_color_buffers(ctx);
+         /* clear software-based alpha buffer(s) */
+         if (ctx->DrawBuffer->UseSoftwareAlphaBuffers
+             && ctx->Color.ColorMask[ACOMP]) {
+            _swrast_clear_alpha_buffers( ctx );
+         }
+      }
+      if (mask & DD_DEPTH_BIT) {
+         _swrast_clear_depth_buffer(ctx);
+      }
+      if (mask & DD_ACCUM_BIT) {
+         _swrast_clear_accum_buffer(ctx);
+      }
+      if (mask & DD_STENCIL_BIT) {
+         _swrast_clear_stencil_buffer(ctx);
+      }
+   }
+
+   RENDER_FINISH(swrast,ctx);
+}
+
+
+/**
+ * Typically called via ctx->Driver.ResizeBuffers().
+ * Reallocate all software-based depth/stencil/accum/etc buffers
+ * to match current window dimensions.
+ */
+void
+_swrast_alloc_buffers( GLframebuffer *buffer )
+{
+   /* Reallocate other buffers if needed. */
+   if (buffer->UseSoftwareDepthBuffer) {
+      _swrast_alloc_depth_buffer( buffer );
+   }
+   if (buffer->UseSoftwareStencilBuffer) {
+      _swrast_alloc_stencil_buffer( buffer );
+   }
+   if (buffer->UseSoftwareAccumBuffer) {
+      _swrast_alloc_accum_buffer( buffer );
+   }
+   if (buffer->UseSoftwareAlphaBuffers) {
+      _swrast_alloc_alpha_buffers( buffer );
+   }
+   if (buffer->UseSoftwareAuxBuffers) {
+      _swrast_alloc_aux_buffers( buffer );
+   }
+}
+
+
+/*
+ * Fallback for ctx->Driver.DrawBuffer()
+ */
+void
+_swrast_DrawBuffer( GLcontext *ctx, GLenum mode )
+{
+   (void) mode;
+   _swrast_use_draw_buffer(ctx);
+}
+
+
+/*
+ * Setup things so that we read/write spans from the user-designated
+ * read buffer (set via glReadPixels).  We usually just have to call
+ * this for glReadPixels, glCopyPixels, etc.
+ */
+void
+_swrast_use_read_buffer( GLcontext *ctx )
+{
+   SWcontext *swrast = SWRAST_CONTEXT(ctx);
+
+   /* Do this so the software-emulated alpha plane span functions work! */
+   swrast->CurrentBufferBit = ctx->Pixel._ReadSrcMask;
+   /* Tell the device driver where to read/write spans */
+   swrast->Driver.SetBuffer(ctx, ctx->ReadBuffer, swrast->CurrentBufferBit);
+}
+
+
+/*
+ * Setup things so that we read/write spans from the default draw buffer.
+ * This is the usual mode that Mesa's software rasterizer operates in.
+ */
+void
+_swrast_use_draw_buffer( GLcontext *ctx )
+{
+   SWcontext *swrast = SWRAST_CONTEXT(ctx);
+
+   /* The user can specify rendering to zero, one, two, or four color
+    * buffers simultaneously with glDrawBuffer()!
+    * We don't expect the span/point/line/triangle functions to deal with
+    * that mess so we'll iterate over the multiple buffers as needed.
+    * But usually we only render to one color buffer at a time.
+    * We set ctx->Color._DriverDrawBuffer to that buffer and tell the
+    * device driver to use that buffer.
+    * Look in s_span.c's multi_write_rgba_span() function to see how
+    * we loop over multiple color buffers when needed.
+    */
+
+   if (ctx->Color._DrawDestMask & DD_FRONT_LEFT_BIT)
+      swrast->CurrentBufferBit = DD_FRONT_LEFT_BIT;
+   else if (ctx->Color._DrawDestMask & DD_BACK_LEFT_BIT)
+      swrast->CurrentBufferBit = DD_BACK_LEFT_BIT;
+   else if (ctx->Color._DrawDestMask & DD_FRONT_RIGHT_BIT)
+      swrast->CurrentBufferBit = DD_FRONT_RIGHT_BIT;
+   else if (ctx->Color._DrawDestMask & DD_BACK_RIGHT_BIT)
+      swrast->CurrentBufferBit = DD_BACK_RIGHT_BIT;
+   else if (ctx->Color._DrawDestMask & DD_AUX0_BIT)
+      swrast->CurrentBufferBit = DD_AUX0_BIT;
+   else if (ctx->Color._DrawDestMask & DD_AUX1_BIT)
+      swrast->CurrentBufferBit = DD_AUX1_BIT;
+   else if (ctx->Color._DrawDestMask & DD_AUX2_BIT)
+      swrast->CurrentBufferBit = DD_AUX2_BIT;
+   else if (ctx->Color._DrawDestMask & DD_AUX3_BIT)
+      swrast->CurrentBufferBit = DD_AUX3_BIT;
+   else
+      /* glDrawBuffer(GL_NONE) */
+      swrast->CurrentBufferBit = DD_FRONT_LEFT_BIT; /* we always have this buffer */
+
+   swrast->Driver.SetBuffer(ctx, ctx->DrawBuffer, swrast->CurrentBufferBit);
+}