[Mesa-dev] [PATCH 04/12] i965: Add a mechanism for sending native primitives into the driver

[Kristian Høgsberg]

The brw_draw_prims() function is the draw entry point into the driver,
and takes struct _mesa_prim for input.  We want to be able to feed
native primitives into the driver, and to that end we introduce
BRW_PRIM_OFFSET, which lets use describe geometry using the native
GEN primitive types.

Signed-off-by: Kristian Høgsberg <krh at bitplanet.net>
---
 src/mesa/drivers/dri/i965/brw_context.h |  2 +-
 src/mesa/drivers/dri/i965/brw_defines.h |  7 +++++++
 src/mesa/drivers/dri/i965/brw_draw.c    | 15 ++++++++++++---
 src/mesa/drivers/dri/i965/brw_vec4_gs.c |  3 ++-
 4 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_context.h b/src/mesa/drivers/dri/i965/brw_context.h
index e23ee4e..7de9b64 100644
--- a/src/mesa/drivers/dri/i965/brw_context.h
+++ b/src/mesa/drivers/dri/i965/brw_context.h
@@ -1767,7 +1767,7 @@ gen8_emit_depth_stencil_hiz(struct brw_context *brw,
 void gen8_hiz_exec(struct brw_context *brw, struct intel_mipmap_tree *mt,
                    unsigned int level, unsigned int layer, enum gen6_hiz_op op);
 
-extern const GLuint prim_to_hw_prim[GL_TRIANGLE_STRIP_ADJACENCY+1];
+uint32_t get_hw_prim_for_gl_prim(int mode);
 
 void
 brw_setup_vec4_key_clip_info(struct brw_context *brw,
diff --git a/src/mesa/drivers/dri/i965/brw_defines.h b/src/mesa/drivers/dri/i965/brw_defines.h
index 3564041..a519629 100644
--- a/src/mesa/drivers/dri/i965/brw_defines.h
+++ b/src/mesa/drivers/dri/i965/brw_defines.h
@@ -77,6 +77,13 @@
 #define _3DPRIM_LINESTRIP_CONT_BF 0x14
 #define _3DPRIM_TRIFAN_NOSTIPPLE  0x15
 
+/* We use this offset to be able to pass native primitive types in struct
+ * _mesa_prim::mode.  Native primitive types are BRW_PRIM_OFFSET +
+ * native_type, which should be different from all GL types and still fit in
+ * the 8 bits avialable. */
+
+#define BRW_PRIM_OFFSET           0x80
+
 #define BRW_ANISORATIO_2     0
 #define BRW_ANISORATIO_4     1
 #define BRW_ANISORATIO_6     2
diff --git a/src/mesa/drivers/dri/i965/brw_draw.c b/src/mesa/drivers/dri/i965/brw_draw.c
index 412c360..f84a2ad 100644
--- a/src/mesa/drivers/dri/i965/brw_draw.c
+++ b/src/mesa/drivers/dri/i965/brw_draw.c
@@ -55,7 +55,7 @@
 
 #define FILE_DEBUG_FLAG DEBUG_PRIMS
 
-const GLuint prim_to_hw_prim[GL_TRIANGLE_STRIP_ADJACENCY+1] = {
+static const GLuint prim_to_hw_prim[GL_TRIANGLE_STRIP_ADJACENCY+1] = {
    _3DPRIM_POINTLIST,
    _3DPRIM_LINELIST,
    _3DPRIM_LINELOOP,
@@ -86,6 +86,15 @@ static const GLenum reduced_prim[GL_POLYGON+1] = {
    GL_TRIANGLES
 };
 
+uint32_t
+get_hw_prim_for_gl_prim(int mode)
+{
+   if (mode >= BRW_PRIM_OFFSET)
+      return mode - BRW_PRIM_OFFSET;
+   else
+      return prim_to_hw_prim[mode];
+}
+
 
 /* When the primitive changes, set a state bit and re-validate.  Not
  * the nicest and would rather deal with this by having all the
@@ -96,7 +105,7 @@ static void brw_set_prim(struct brw_context *brw,
                          const struct _mesa_prim *prim)
 {
    struct gl_context *ctx = &brw->ctx;
-   uint32_t hw_prim = prim_to_hw_prim[prim->mode];
+   uint32_t hw_prim = get_hw_prim_for_gl_prim(prim->mode);
 
    DBG("PRIM: %s\n", _mesa_lookup_enum_by_nr(prim->mode));
 
@@ -133,7 +142,7 @@ static void gen6_set_prim(struct brw_context *brw,
 
    DBG("PRIM: %s\n", _mesa_lookup_enum_by_nr(prim->mode));
 
-   hw_prim = prim_to_hw_prim[prim->mode];
+   hw_prim = get_hw_prim_for_gl_prim(prim->mode);
 
    if (hw_prim != brw->primitive) {
       brw->primitive = hw_prim;
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_gs.c b/src/mesa/drivers/dri/i965/brw_vec4_gs.c
index 6428291..12cb943 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_gs.c
+++ b/src/mesa/drivers/dri/i965/brw_vec4_gs.c
@@ -217,7 +217,8 @@ do_gs_prog(struct brw_context *brw,
    /* URB entry sizes are stored as a multiple of 64 bytes. */
    c.prog_data.base.urb_entry_size = ALIGN(output_size_bytes, 64) / 64;
 
-   c.prog_data.output_topology = prim_to_hw_prim[gp->program.OutputType];
+   c.prog_data.output_topology =
+      get_hw_prim_for_gl_prim(gp->program.OutputType);
 
    brw_compute_vue_map(brw, &c.input_vue_map, c.key.input_varyings);
 
-- 
2.0.0