selection/feedback support

1 files changed, 306 insertions, 0 deletions

diff --git a/src/mesa/state_tracker/st_cb_feedback.c b/src/mesa/state_tracker/st_cb_feedback.c
new file mode 100644
index 0000000000..b97b2bb027
--- /dev/null
+++ b/src/mesa/state_tracker/st_cb_feedback.c
@@ -0,0 +1,306 @@
+/**************************************************************************
+ * 
+ * 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.
+ * 
+ **************************************************************************/
+
+/**
+ * GL_SELECT and GL_FEEDBACK render modes.
+ * Basically, we use a private instance of the 'draw' module for doing
+ * selection/feedback.  It would be nice to use the transform_feedback
+ * hardware feature, but it's defined as happening pre-clip and we want
+ * post-clipped primitives.  Also, there's concerns about the efficiency
+ * of using the hardware for this anyway.
+ *
+ * Authors:
+ *   Brian Paul
+ */
+
+#include "main/imports.h"
+#include "main/context.h"
+#include "main/feedback.h"
+#include "main/macros.h"
+
+#include "vbo/vbo.h"
+#include "vbo/vbo_context.h"
+
+#include "st_context.h"
+#include "st_atom.h"
+#include "st_draw.h"
+#include "st_cb_feedback.h"
+#include "st_cb_bufferobjects.h"
+
+#include "pipe/p_context.h"
+#include "pipe/p_defines.h"
+#include "pipe/p_winsys.h"
+#include "pipe/tgsi/exec/tgsi_attribs.h"
+#include "vf/vf.h"
+
+#include "pipe/draw/draw_context.h"
+#include "pipe/draw/draw_private.h"
+
+
+/**
+ * This is actually used for both feedback and selection.
+ */
+struct feedback_stage
+{
+   struct draw_stage stage;   /**< Base class */
+   GLcontext *ctx;            /**< Rendering context */
+   GLboolean reset_stipple_counter;
+};
+
+
+/**********************************************************************
+ * GL Feedback functions
+ **********************************************************************/
+
+static INLINE struct feedback_stage *
+feedback_stage( struct draw_stage *stage )
+{
+   return (struct feedback_stage *)stage;
+}
+
+
+static void
+feedback_vertex(GLcontext *ctx, const struct draw_context *draw,
+                const struct vertex_header *v)
+{
+   GLfloat win[4];
+   const GLfloat *color, *texcoord;
+   const GLfloat ci = 0;
+   GLuint slot;
+
+   win[0] = v->data[0][0];
+   win[1] = v->data[0][1];
+   win[2] = v->data[0][2];
+   win[3] = 1.0F / v->data[0][3];
+
+   slot = draw->vertex_info.attrib_to_slot[TGSI_ATTRIB_COLOR0];
+   if (slot)
+      color = v->data[slot];
+   else
+      color = ctx->Current.Attrib[VERT_ATTRIB_COLOR0];
+
+   slot = draw->vertex_info.attrib_to_slot[TGSI_ATTRIB_TEX0];
+   if (slot)
+      texcoord = v->data[slot];
+   else
+      texcoord = ctx->Current.Attrib[VERT_ATTRIB_TEX0];
+
+   _mesa_feedback_vertex(ctx, win, color, ci, texcoord);
+}
+
+
+static void
+feedback_tri( struct draw_stage *stage, struct prim_header *prim )
+{
+   struct feedback_stage *fs = feedback_stage(stage);
+   struct draw_context *draw = stage->draw;
+   FEEDBACK_TOKEN(fs->ctx, (GLfloat) GL_POLYGON_TOKEN);
+   FEEDBACK_TOKEN(fs->ctx, (GLfloat) 3); /* three vertices */
+   feedback_vertex(fs->ctx, draw, prim->v[0]);
+   feedback_vertex(fs->ctx, draw, prim->v[1]);
+   feedback_vertex(fs->ctx, draw, prim->v[2]);
+}
+
+
+static void
+feedback_line( struct draw_stage *stage, struct prim_header *prim )
+{
+   struct feedback_stage *fs = feedback_stage(stage);
+   struct draw_context *draw = stage->draw;
+   if (fs->reset_stipple_counter) {
+      FEEDBACK_TOKEN(fs->ctx, (GLfloat) GL_LINE_RESET_TOKEN);
+      fs->reset_stipple_counter = GL_FALSE;
+   }
+   else {
+      FEEDBACK_TOKEN(fs->ctx, (GLfloat) GL_LINE_TOKEN);
+   }
+   feedback_vertex(fs->ctx, draw, prim->v[0]);
+   feedback_vertex(fs->ctx, draw, prim->v[1]);
+}
+
+
+static void
+feedback_point( struct draw_stage *stage, struct prim_header *prim )
+{
+   struct feedback_stage *fs = feedback_stage(stage);
+   struct draw_context *draw = stage->draw;
+   FEEDBACK_TOKEN(fs->ctx, (GLfloat) GL_POINT_TOKEN);
+   feedback_vertex(fs->ctx, draw, prim->v[0]);
+}
+
+
+static void
+feedback_end( struct draw_stage *stage )
+{
+   /* no-op */
+}
+
+
+static void
+feedback_begin( struct draw_stage *stage )
+{
+   /* no-op */
+}
+
+
+static void
+feedback_reset_stipple_counter( struct draw_stage *stage )
+{
+   struct feedback_stage *fs = feedback_stage(stage);
+   fs->reset_stipple_counter = GL_TRUE;
+}
+
+
+/**
+ * Create GL feedback drawing stage.
+ */
+static struct draw_stage *
+draw_glfeedback_stage(GLcontext *ctx, struct draw_context *draw)
+{
+   struct feedback_stage *fs = CALLOC_STRUCT(feedback_stage);
+
+   fs->stage.draw = draw;
+   fs->stage.next = NULL;
+   fs->stage.begin = feedback_begin;
+   fs->stage.point = feedback_point;
+   fs->stage.line = feedback_line;
+   fs->stage.tri = feedback_tri;
+   fs->stage.end = feedback_end;
+   fs->stage.reset_stipple_counter = feedback_reset_stipple_counter;
+   fs->ctx = ctx;
+
+   return &fs->stage;
+}
+
+
+
+/**********************************************************************
+ * GL Selection functions
+ **********************************************************************/
+
+static void
+select_tri( struct draw_stage *stage, struct prim_header *prim )
+{
+   struct feedback_stage *fs = feedback_stage(stage);
+   _mesa_update_hitflag( fs->ctx, prim->v[0]->data[0][2] );
+   _mesa_update_hitflag( fs->ctx, prim->v[1]->data[0][2] );
+   _mesa_update_hitflag( fs->ctx, prim->v[2]->data[0][2] );
+}
+
+static void
+select_line( struct draw_stage *stage, struct prim_header *prim )
+{
+   struct feedback_stage *fs = feedback_stage(stage);
+   _mesa_update_hitflag( fs->ctx, prim->v[0]->data[0][2] );
+   _mesa_update_hitflag( fs->ctx, prim->v[1]->data[0][2] );
+}
+
+
+static void
+select_point( struct draw_stage *stage, struct prim_header *prim )
+{
+   struct feedback_stage *fs = feedback_stage(stage);
+   _mesa_update_hitflag( fs->ctx, prim->v[0]->data[0][2] );
+}
+
+
+static void
+select_begin( struct draw_stage *stage )
+{
+   /* no-op */
+}
+
+
+static void
+select_end( struct draw_stage *stage )
+{
+   /* no-op */
+}
+
+
+static void
+select_reset_stipple_counter( struct draw_stage *stage )
+{
+   /* no-op */
+}
+
+
+/**
+ * Create GL selection mode drawing stage.
+ */
+static struct draw_stage *
+draw_glselect_stage(GLcontext *ctx, struct draw_context *draw)
+{
+   struct feedback_stage *fs = CALLOC_STRUCT(feedback_stage);
+
+   fs->stage.draw = draw;
+   fs->stage.next = NULL;
+   fs->stage.begin = select_begin;
+   fs->stage.point = select_point;
+   fs->stage.line = select_line;
+   fs->stage.tri = select_tri;
+   fs->stage.end = select_end;
+   fs->stage.reset_stipple_counter = select_reset_stipple_counter;
+   fs->ctx = ctx;
+
+   return &fs->stage;
+}
+
+
+static void
+st_RenderMode(GLcontext *ctx, GLenum newMode )
+{
+   struct st_context *st = ctx->st;
+   struct vbo_context *vbo = (struct vbo_context *) ctx->swtnl_im;
+   struct draw_context *draw = st->draw;
+
+   if (newMode == GL_RENDER) {
+      /* restore normal VBO draw function */
+      vbo->draw_prims = st_draw_vbo;
+   }
+   else if (newMode == GL_SELECT) {
+      if (!st->selection_stage)
+         st->selection_stage = draw_glselect_stage(ctx, draw);
+      draw_set_setup_stage(draw, st->selection_stage);
+      /* Plug in new vbo draw function */
+      vbo->draw_prims = st_feedback_draw_vbo;
+   }
+   else {
+      if (!st->feedback_stage)
+         st->feedback_stage = draw_glfeedback_stage(ctx, draw);
+      draw_set_setup_stage(draw, st->feedback_stage);
+      /* Plug in new vbo draw function */
+      vbo->draw_prims = st_feedback_draw_vbo;
+   }
+}
+
+
+
+void st_init_feedback_functions(struct dd_function_table *functions)
+{
+   functions->RenderMode = st_RenderMode;
+}