[Mesa-dev] [PATCH 1/3] tgsi: add TXF support.

[Dave Airlie]

From: Dave Airlie <airlied at redhat.com>

This is a straight texel fetch with no filtering or clamping. It uses
integers to specify the i/j/k (from EXT_gpu_shader4).

To enable this I had to add another hook into the tgsi sampler so that
we could easily bypass all the filtering sample does.

Signed-off-by: Dave Airlie <airlied at redhat.com>
---
 src/gallium/auxiliary/tgsi/tgsi_exec.c |   52 +++++++++++++++++++++++++++++++-
 src/gallium/auxiliary/tgsi/tgsi_exec.h |    3 ++
 2 files changed, 54 insertions(+), 1 deletions(-)

diff --git a/src/gallium/auxiliary/tgsi/tgsi_exec.c b/src/gallium/auxiliary/tgsi/tgsi_exec.c
index bfddf0d..88c88e2 100644
--- a/src/gallium/auxiliary/tgsi/tgsi_exec.c
+++ b/src/gallium/auxiliary/tgsi/tgsi_exec.c
@@ -1594,6 +1594,9 @@ store_dest(struct tgsi_exec_machine *mach,
 #define FETCH(VAL,INDEX,CHAN)\
     fetch_source(mach, VAL, &inst->Src[INDEX], CHAN, TGSI_EXEC_DATA_FLOAT)
 
+#define IFETCH(VAL,INDEX,CHAN)\
+    fetch_source(mach, VAL, &inst->Src[INDEX], CHAN, TGSI_EXEC_DATA_INT)
+
 
 /**
  * Execute ARB-style KIL which is predicated by a src register.
@@ -1920,6 +1923,53 @@ exec_txd(struct tgsi_exec_machine *mach,
    }
 }
 
+
+static void
+exec_txf(struct tgsi_exec_machine *mach,
+	 const struct tgsi_full_instruction *inst)
+{
+   struct tgsi_sampler *sampler;
+   const uint unit = inst->Src[1].Register.Index;
+   union tgsi_exec_channel r[4];
+   uint chan;
+   float rgba[NUM_CHANNELS][QUAD_SIZE];
+   int j;
+
+   IFETCH(&r[3], 0, CHAN_W);
+
+   switch(inst->Texture.Texture) {
+   case TGSI_TEXTURE_3D:
+   case TGSI_TEXTURE_2D_ARRAY:
+      IFETCH(&r[2], 0, CHAN_Z);
+   case TGSI_TEXTURE_2D:
+   case TGSI_TEXTURE_RECT:
+   case TGSI_TEXTURE_SHADOW2D:
+   case TGSI_TEXTURE_SHADOWRECT:
+   case TGSI_TEXTURE_1D_ARRAY:
+      IFETCH(&r[1], 0, CHAN_Y);
+   case TGSI_TEXTURE_1D:
+   case TGSI_TEXTURE_SHADOW1D:
+      IFETCH(&r[0], 0, CHAN_X);
+   }      
+
+   sampler = mach->Samplers[unit];
+   sampler->get_texel(sampler, r[0].i, r[1].i, r[2].i, r[3].i,
+		      rgba);
+
+   for (j = 0; j < 4; j++) {
+      r[0].f[j] = rgba[0][j];
+      r[1].f[j] = rgba[1][j];
+      r[2].f[j] = rgba[2][j];
+      r[3].f[j] = rgba[3][j];
+   }
+
+   for (chan = 0; chan < NUM_CHANNELS; chan++) {
+      if (inst->Dst[0].Register.WriteMask & (1 << chan)) {
+         store_dest(mach, &r[chan], &inst->Dst[0], inst, chan, TGSI_EXEC_DATA_FLOAT);
+      }
+   }
+}
+
 static void
 exec_txq(struct tgsi_exec_machine *mach,
          const struct tgsi_full_instruction *inst)
@@ -3742,7 +3792,7 @@ exec_instruction(
       break;
 
    case TGSI_OPCODE_TXF:
-      assert (0);
+      exec_txf(mach, inst);
       break;
 
    case TGSI_OPCODE_TXQ:
diff --git a/src/gallium/auxiliary/tgsi/tgsi_exec.h b/src/gallium/auxiliary/tgsi/tgsi_exec.h
index 2162a07..3f6964c 100644
--- a/src/gallium/auxiliary/tgsi/tgsi_exec.h
+++ b/src/gallium/auxiliary/tgsi/tgsi_exec.h
@@ -92,6 +92,9 @@ struct tgsi_sampler
                        float rgba[NUM_CHANNELS][QUAD_SIZE]);
    void (*get_dims)(struct tgsi_sampler *sampler, int level,
 		    int dims[4]);
+   void (*get_texel)(struct tgsi_sampler *sampler, const int i[QUAD_SIZE],
+		     const int j[QUAD_SIZE], const int k[QUAD_SIZE],
+		     const int lod[QUAD_SIZE], float rgba[NUM_CHANNELS][QUAD_SIZE]);
 };
 
 #define TGSI_EXEC_NUM_TEMPS       128
-- 
1.7.6