Implemented support for software-based AUX color buffers.

Only available with Xlib driver for now.
Assorted clean-ups related to Draw/ReadBuffer().
Renamed FRONT_LEFT_BIT -> DD_FRONT_LEFT_BIT, etc.

1 files changed, 121 insertions, 0 deletions

diff --git a/src/mesa/swrast/s_auxbuffer.c b/src/mesa/swrast/s_auxbuffer.c
new file mode 100644
index 00000000000..ca36d90ded8
--- /dev/null
+++ b/src/mesa/swrast/s_auxbuffer.c
@@ -0,0 +1,121 @@
+/*
+ * 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 "imports.h"
+
+#include "s_auxbuffer.h"
+#include "s_context.h"
+
+
+
+void
+_swrast_alloc_aux_buffers( GLframebuffer *buffer )
+{
+   GLuint i;
+
+   for (i = 0; i < buffer->Visual.numAuxBuffers; i++) {
+      if (buffer->AuxBuffers[i]) {
+         _mesa_free(buffer->AuxBuffers[i]);
+         buffer->AuxBuffers[i] = NULL;
+      }
+
+      buffer->AuxBuffers[i] = _mesa_malloc(buffer->Width * buffer->Height
+                                           * 4 * sizeof(GLchan));
+   }
+}
+
+
+
+/* RGBA */
+#define NAME(PREFIX) PREFIX##_aux
+#define SPAN_VARS \
+   const SWcontext *swrast = SWRAST_CONTEXT(ctx);
+#define INIT_PIXEL_PTR(P, X, Y) \
+   GLchan *P = swrast->CurAuxBuffer + ((Y) * ctx->DrawBuffer->Width + (X)) * 4; \
+   assert(swrast->CurAuxBuffer);
+
+#define INC_PIXEL_PTR(P) P += 4
+#if CHAN_TYPE == GL_FLOAT
+#define STORE_RGB_PIXEL(P, X, Y, R, G, B) \
+   P[0] = MAX2((R), 0.0F); \
+   P[1] = MAX2((G), 0.0F); \
+   P[2] = MAX2((B), 0.0F); \
+   P[3] = CHAN_MAXF
+#define STORE_RGBA_PIXEL(P, X, Y, R, G, B, A) \
+   P[0] = MAX2((R), 0.0F); \
+   P[1] = MAX2((G), 0.0F); \
+   P[2] = MAX2((B), 0.0F); \
+   P[3] = CLAMP((A), 0.0F, CHAN_MAXF)
+#else
+#define STORE_RGB_PIXEL(P, X, Y, R, G, B) \
+   P[0] = R;  P[1] = G;  P[2] = B;  P[3] = CHAN_MAX
+#define STORE_RGBA_PIXEL(P, X, Y, R, G, B, A) \
+   P[0] = R;  P[1] = G;  P[2] = B;  P[3] = A
+#endif
+#define FETCH_RGBA_PIXEL(R, G, B, A, P) \
+   R = P[0];  G = P[1];  B = P[2];  A = P[3]
+#include "swrast/s_spantemp.h"
+
+
+
+/**
+ * Called from driver's SetBuffer() function to choose an aux buffer.
+ */
+void
+_swrast_use_aux_buffer(GLcontext *ctx, GLframebuffer *buffer, GLuint bufferBit)
+{
+   SWcontext *swrast = SWRAST_CONTEXT(ctx);
+
+   switch (bufferBit) {
+   case DD_AUX0_BIT:
+      ASSERT(buffer->Visual.numAuxBuffers >= 1);
+      swrast->CurAuxBuffer = ctx->DrawBuffer->AuxBuffers[0];
+      break;
+   case DD_AUX1_BIT:
+      ASSERT(buffer->Visual.numAuxBuffers >= 2);
+      swrast->CurAuxBuffer = ctx->DrawBuffer->AuxBuffers[1];
+      break;
+   case DD_AUX2_BIT:
+      ASSERT(buffer->Visual.numAuxBuffers >= 3);
+      swrast->CurAuxBuffer = ctx->DrawBuffer->AuxBuffers[2];
+      break;
+   case DD_AUX3_BIT:
+      ASSERT(buffer->Visual.numAuxBuffers >= 4);
+      swrast->CurAuxBuffer = ctx->DrawBuffer->AuxBuffers[3];
+      break;
+   default:
+      swrast->CurAuxBuffer = NULL;
+   }
+
+   swrast->Driver.WriteRGBASpan = write_rgba_span_aux;
+   swrast->Driver.WriteRGBSpan = write_rgb_span_aux;
+   swrast->Driver.WriteMonoRGBASpan = write_monorgba_span_aux;
+   swrast->Driver.WriteRGBAPixels = write_rgba_pixels_aux;
+   swrast->Driver.WriteMonoRGBAPixels = write_monorgba_pixels_aux;
+   swrast->Driver.ReadRGBASpan = read_rgba_span_aux;
+   swrast->Driver.ReadRGBAPixels = read_rgba_pixels_aux;
+}
+