glRasterPos function

1 files changed, 350 insertions, 0 deletions

diff --git a/src/mesa/state_tracker/st_cb_rasterpos.c b/src/mesa/state_tracker/st_cb_rasterpos.c
new file mode 100644
index 0000000000..5040c21e51
--- /dev/null
+++ b/src/mesa/state_tracker/st_cb_rasterpos.c
@@ -0,0 +1,350 @@
+/**************************************************************************
+ * 
+ * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
+ * 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, sub license, 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 (including the
+ * next paragraph) 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 NON-INFRINGEMENT.
+ * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS 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.
+ * 
+ **************************************************************************/
+
+ /*
+  * Authors:
+  *   Brian Paul
+  */
+
+#include "main/imports.h"
+#include "main/macros.h"
+
+#include "st_context.h"
+#include "st_atom.h"
+#include "st_draw.h"
+#include "st_program.h"
+#include "st_cb_rasterpos.h"
+#include "st_draw.h"
+#include "st_format.h"
+#include "pipe/p_context.h"
+#include "pipe/p_defines.h"
+#include "pipe/p_winsys.h"
+#include "pipe/tgsi/exec/tgsi_attribs.h"
+#include "shader/prog_instruction.h"
+#include "vf/vf.h"
+
+
+
+static void
+setup_vertex_attribs(GLcontext *ctx)
+{
+   struct pipe_context *pipe = ctx->st->pipe;
+   const uint inputAttrs = ctx->st->state.vs.inputs_read;
+   uint attr;
+
+   /* all attributes come from the default attribute buffer */
+   {
+      struct pipe_vertex_buffer vbuffer;
+      vbuffer.buffer = ctx->st->default_attrib_buffer;
+      vbuffer.buffer_offset = 0;
+      vbuffer.pitch = 0; /* must be zero! */
+      vbuffer.max_index = 1;
+      pipe->set_vertex_buffer(pipe, 0, &vbuffer);
+   }
+
+   for (attr = 0; attr < 16; attr++) {
+      struct pipe_vertex_element velement;
+
+      if (inputAttrs & (1 << attr)) {
+         velement.src_offset = attr * 4 * sizeof(GLfloat);
+         velement.vertex_buffer_index = 0;
+         velement.dst_offset = 0;
+         velement.src_format = PIPE_FORMAT_R32G32B32A32_FLOAT;
+         pipe->set_vertex_element(pipe, attr, &velement);
+      }
+   }
+}
+
+
+static void
+setup_feedback(GLcontext *ctx)
+{
+   struct pipe_context *pipe = ctx->st->pipe;
+   const uint outputAttrs = ctx->st->state.vs.outputs_written;
+   struct pipe_feedback_state feedback;
+   uint i;
+
+   memset(&feedback, 0, sizeof(feedback));
+   feedback.enabled = 1;
+   feedback.interleaved = 1;
+   feedback.discard = 1;
+   feedback.num_attribs = 0;
+
+   for (i = 0; i < TGSI_ATTRIB_VAR0; i++) {
+      if ((1 << i) & outputAttrs) {
+         feedback.attrib[feedback.num_attribs] = i;
+         feedback.size[feedback.num_attribs] = 4;
+         feedback.num_attribs++;
+      }
+   }
+
+   pipe->set_feedback_state(pipe, &feedback);
+}
+
+
+
+
+
+/**
+ * Clip a point against the view volume.
+ *
+ * \param v vertex vector describing the point to clip.
+ * 
+ * \return zero if outside view volume, or one if inside.
+ */
+static GLuint
+viewclip_point( const GLfloat v[] )
+{
+   if (   v[0] > v[3] || v[0] < -v[3]
+       || v[1] > v[3] || v[1] < -v[3]
+       || v[2] > v[3] || v[2] < -v[3] ) {
+      return 0;
+   }
+   else {
+      return 1;
+   }
+}
+
+
+/**
+ * Clip a point against the far/near Z clipping planes.
+ *
+ * \param v vertex vector describing the point to clip.
+ * 
+ * \return zero if outside view volume, or one if inside.
+ */
+static GLuint
+viewclip_point_z( const GLfloat v[] )
+{
+   if (v[2] > v[3] || v[2] < -v[3] ) {
+      return 0;
+   }
+   else {
+      return 1;
+   }
+}
+
+
+/**
+ * Clip a point against the user clipping planes.
+ * 
+ * \param ctx GL context.
+ * \param v vertex vector describing the point to clip.
+ * 
+ * \return zero if the point was clipped, or one otherwise.
+ */
+static GLuint
+userclip_point( GLcontext *ctx, const GLfloat v[] )
+{
+   GLuint p;
+
+   for (p = 0; p < ctx->Const.MaxClipPlanes; p++) {
+      if (ctx->Transform.ClipPlanesEnabled & (1 << p)) {
+	 GLfloat dot = v[0] * ctx->Transform._ClipUserPlane[p][0]
+		     + v[1] * ctx->Transform._ClipUserPlane[p][1]
+		     + v[2] * ctx->Transform._ClipUserPlane[p][2]
+		     + v[3] * ctx->Transform._ClipUserPlane[p][3];
+         if (dot < 0.0F) {
+            return 0;
+         }
+      }
+   }
+
+   return 1;
+}
+
+
+/**
+ * Update the current raster position.
+ * Do clip testing, etc. here.
+ */
+static void
+update_rasterpos(GLcontext *ctx,
+                 const float clipPos[4],
+                 const float color0[4],
+                 const float color1[4],
+                 const float *tex)
+{
+   uint i;
+   float d, ndc[3];
+
+   /* clip to view volume */
+   if (ctx->Transform.RasterPositionUnclipped) {
+      /* GL_IBM_rasterpos_clip: only clip against Z */
+      if (viewclip_point_z(clipPos) == 0) {
+         ctx->Current.RasterPosValid = GL_FALSE;
+         return;
+      }
+   }
+   else if (viewclip_point(clipPos) == 0) {
+      /* Normal OpenGL behaviour */
+      ctx->Current.RasterPosValid = GL_FALSE;
+      return;
+   }
+
+   /* clip to user clipping planes */
+   if (ctx->Transform.ClipPlanesEnabled && !userclip_point(ctx, clipPos)) {
+      ctx->Current.RasterPosValid = GL_FALSE;
+      return;
+   }
+
+
+   /*
+    * update current raster position
+    */
+   /* ndc = clip / W */
+   d = (clipPos[3] == 0.0F) ? 1.0F : 1.0F / clipPos[3];
+   ndc[0] = clipPos[0] * d;
+   ndc[1] = clipPos[1] * d;
+   ndc[2] = clipPos[2] * d;
+   /* wincoord = viewport_mapping(ndc) */
+   ctx->Current.RasterPos[0] = (ndc[0] * ctx->Viewport._WindowMap.m[MAT_SX]
+                                + ctx->Viewport._WindowMap.m[MAT_TX]);
+   ctx->Current.RasterPos[1] = (ndc[1] * ctx->Viewport._WindowMap.m[MAT_SY]
+                                + ctx->Viewport._WindowMap.m[MAT_TY]);
+   ctx->Current.RasterPos[2] = (ndc[2] * ctx->Viewport._WindowMap.m[MAT_SZ]
+                                + ctx->Viewport._WindowMap.m[MAT_TZ])
+                               / ctx->DrawBuffer->_DepthMaxF;
+   ctx->Current.RasterPos[3] = clipPos[3];
+
+   /* compute raster distance */
+   if (ctx->Fog.FogCoordinateSource == GL_FOG_COORDINATE_EXT)
+      ctx->Current.RasterDistance = ctx->Current.Attrib[VERT_ATTRIB_FOG][0];
+   else {
+#if 0
+      /* XXX we don't have an eye coord! */
+      ctx->Current.RasterDistance =
+         SQRTF( eye[0]*eye[0] + eye[1]*eye[1] + eye[2]*eye[2] );
+#endif
+   }
+
+   /* colors and texcoords */
+   COPY_4FV(ctx->Current.RasterColor, color0);
+   COPY_4FV(ctx->Current.RasterSecondaryColor, color1);
+   for (i = 0; i < ctx->Const.MaxTextureCoordUnits; i++) {
+      COPY_4FV(ctx->Current.RasterTexCoords + i, tex + i *4);
+   }
+
+   ctx->Current.RasterPosValid = GL_TRUE;
+}
+
+
+
+static void
+st_RasterPos(GLcontext *ctx, const GLfloat v[4])
+{
+   struct pipe_context *pipe = ctx->st->pipe;
+   float *buf_map;
+   struct pipe_feedback_buffer fb_buf;
+
+   st_validate_state(ctx->st);
+
+   /* setup vertex buffers */
+   setup_vertex_attribs(ctx);
+
+   /*
+    * Load the default attribute buffer with current attribs.
+    */
+   {
+      struct pipe_buffer_handle *buf = ctx->st->default_attrib_buffer;
+      const unsigned size = sizeof(ctx->Current.Attrib);
+      const void *data = ctx->Current.Attrib;
+      /* colors, texcoords, etc */
+      pipe->winsys->buffer_data(pipe->winsys, buf, size, data);
+      /* position */
+      pipe->winsys->buffer_subdata(pipe->winsys, buf,
+                                   0, /* offset */
+                                   4 * sizeof(float), /* size */
+                                   v); /* data */
+   }
+
+
+   /* setup feedback state */
+   setup_feedback(ctx);
+
+   /* setup vertex feedback buffer */
+   {
+      fb_buf.size = 8 * 4 * sizeof(float);
+      fb_buf.buffer = pipe->winsys->buffer_create(pipe->winsys, 0);
+      fb_buf.start_offset = 0;
+      pipe->winsys->buffer_data(pipe->winsys, fb_buf.buffer,
+                                fb_buf.size,
+                                NULL); /* data */
+      pipe->set_feedback_buffer(pipe, 0, &fb_buf);
+   }
+
+
+   /* draw a point */
+   pipe->draw_arrays(pipe, GL_POINTS, 0, 1);
+
+   /* get feedback */
+   buf_map = (float *) pipe->winsys->buffer_map(pipe->winsys, fb_buf.buffer,
+                                                PIPE_BUFFER_FLAG_READ);
+
+   /* extract values and update rasterpos state */
+   {
+      const uint outputAttrs = ctx->st->state.vs.outputs_written;
+      const float *pos, *color0, *color1, *tex0;
+      float *buf = buf_map;
+
+      assert(outputAttrs & (1 << TGSI_ATTRIB_POS));
+      pos = buf;
+      buf += 4;
+
+      if (outputAttrs & (1 << TGSI_ATTRIB_COLOR0)) {
+         color0 = buf;
+         buf += 4;
+      }
+      else {
+         color0 = ctx->Current.Attrib[VERT_ATTRIB_COLOR0];
+      }
+
+      if (outputAttrs & (1 << TGSI_ATTRIB_COLOR1)) {
+         color1 = buf;
+         buf += 4;
+      }
+      else {
+         color1 = ctx->Current.Attrib[VERT_ATTRIB_COLOR1];
+      }
+
+      update_rasterpos(ctx, pos, color0, color1, tex0);
+   }
+
+
+   /* free vertex feedback buffer */
+   pipe->winsys->buffer_unmap(pipe->winsys, fb_buf.buffer);
+   pipe->winsys->buffer_unreference(pipe->winsys, &fb_buf.buffer);
+
+   /* restore pipe state */
+   pipe->set_feedback_state(pipe, &ctx->st->state.feedback);
+}
+
+
+void st_init_rasterpos_functions(struct dd_function_table *functions)
+{
+   functions->RasterPos = st_RasterPos;
+}