swrast: Always use MapTextureImage for mapping textures for swrast.

Now that everything goes through ImageSlices[], we can rely on the
driver's existing texture mapping function.

A big block of code goes away on Radeon that looks like it was to deal with
the validate that happened at SpanRenderStart, which no longer occurs since we
don't need validation for the MapTextureImage hook.

v2: Rewrite comment about ImageSlices, fix duplicated swImages, touch up
    unmap loop.

Reviewed-by: Kenneth Graunke <[email protected]> (v1)
Reviewed-by: Brian Paul <[email protected]>

2 files changed, 56 insertions, 12 deletions

diff --git a/src/mesa/swrast/s_context.h b/src/mesa/swrast/s_context.h
index 38015483597..2525e8e2d38 100644
--- a/src/mesa/swrast/s_context.h
+++ b/src/mesa/swrast/s_context.h
@@ -148,8 +148,14 @@ struct swrast_texture_image
     * between all slices.
     */
    GLint RowStride;
-   void **ImageSlices;          /**< if 3D texture: array [Depth] of offsets to
-                                     each 2D slice in 'Data', in texels */
+   /**
+    * When a texture image is mapped for swrast, this array contains pointers
+    * to the beginning of each slice.
+    *
+    * For swrast-allocated textures, these pointers will always stay
+    * initialized to point within Buffer.
+    */
+   void **ImageSlices;
    GLubyte *Map;		/**< Pointer to mapped image memory */
 
    /** Malloc'd texture memory */
diff --git a/src/mesa/swrast/s_texture.c b/src/mesa/swrast/s_texture.c
index 1783d9c477f..27803c55330 100644
--- a/src/mesa/swrast/s_texture.c
+++ b/src/mesa/swrast/s_texture.c
@@ -266,12 +266,42 @@ _swrast_map_texture(struct gl_context *ctx, struct gl_texture_object *texObj)
    for (face = 0; face < faces; face++) {
       for (level = texObj->BaseLevel; level < MAX_TEXTURE_LEVELS; level++) {
          struct gl_texture_image *texImage = texObj->Image[face][level];
-         if (texImage) {
-            struct swrast_texture_image *swImage =
-               swrast_texture_image(texImage);
+         struct swrast_texture_image *swImage = swrast_texture_image(texImage);
+         unsigned int i;
+
+         if (!texImage)
+            continue;
+
+         /* In the case of a swrast-allocated texture buffer, the ImageSlices
+          * and RowStride are always available.
+          */
+         if (swImage->Buffer) {
+            assert(swImage->ImageSlices[0] == swImage->Buffer);
+            continue;
+         }
 
-            /* XXX we'll eventually call _swrast_map_teximage() here */
-            swImage->Map = swImage->Buffer;
+         for (i = 0; i < texture_slices(texImage); i++) {
+            GLubyte *map;
+            GLint rowStride;
+
+            if (swImage->ImageSlices[i])
+               continue;
+
+            ctx->Driver.MapTextureImage(ctx, texImage, i,
+                                        0, 0,
+                                        texImage->Width, texImage->Height,
+                                        GL_MAP_READ_BIT | GL_MAP_WRITE_BIT,
+                                        &map, &rowStride);
+
+            swImage->ImageSlices[i] = map;
+            /* A swrast-using driver has to return the same rowstride for
+             * every slice of the same texture, since we don't track them
+             * separately.
+             */
+            if (i == 0)
+               swImage->RowStride = rowStride;
+            else
+               assert(swImage->RowStride == rowStride);
          }
       }
    }
@@ -287,12 +317,20 @@ _swrast_unmap_texture(struct gl_context *ctx, struct gl_texture_object *texObj)
    for (face = 0; face < faces; face++) {
       for (level = texObj->BaseLevel; level < MAX_TEXTURE_LEVELS; level++) {
          struct gl_texture_image *texImage = texObj->Image[face][level];
-         if (texImage) {
-            struct swrast_texture_image *swImage
-               = swrast_texture_image(texImage);
+         struct swrast_texture_image *swImage = swrast_texture_image(texImage);
+         unsigned int i;
+
+         if (!texImage)
+            continue;
+
+         if (swImage->Buffer)
+            return;
 
-            /* XXX we'll eventually call _swrast_unmap_teximage() here */
-            swImage->Map = NULL;
+         for (i = 0; i < texture_slices(texImage); i++) {
+            if (swImage->ImageSlices[i]) {
+               ctx->Driver.UnmapTextureImage(ctx, texImage, i);
+               swImage->ImageSlices[i] = NULL;
+            }
          }
       }
    }