mesa: add swrast_texture_image::Buffer

In the past, swrast_texture_image::Data has been overloaded.  It could
either point to malloc'd memory storing texture data, or it could point
to a current mapping of GPU memory.

Now, Buffer always points to malloc'd memory (if we're not using GPU
memory) and Data always points to mapped memory.  The next step would
be to rename Data -> Map.

This change also involves adding swrast functions for mapping textures
and renderbuffers prior to rendering to setup the Data pointer.  Plus,
corresponding functions to unmap texures and renderbuffers.  This is
very much like similar code in the dri drivers.

1 files changed, 143 insertions, 8 deletions

diff --git a/src/mesa/swrast/s_texture.c b/src/mesa/swrast/s_texture.c
index df371c30e3c..80c3070c941 100644
--- a/src/mesa/swrast/s_texture.c
+++ b/src/mesa/swrast/s_texture.c
@@ -76,9 +76,9 @@ _swrast_alloc_texture_image_buffer(struct gl_context *ctx,
    assert(texImage->Height == height);
    assert(texImage->Depth == depth);
 
-   assert(!swImg->Data);
-   swImg->Data = _mesa_align_malloc(bytes, 512);
-   if (!swImg->Data)
+   assert(!swImg->Buffer);
+   swImg->Buffer = _mesa_align_malloc(bytes, 512);
+   if (!swImg->Buffer)
       return GL_FALSE;
 
    /* RowStride and ImageOffsets[] describe how to address texels in 'Data' */
@@ -128,9 +128,9 @@ _swrast_free_texture_image_buffer(struct gl_context *ctx,
                                   struct gl_texture_image *texImage)
 {
    struct swrast_texture_image *swImage = swrast_texture_image(texImage);
-   if (swImage->Data) {
-      _mesa_align_free(swImage->Data);
-      swImage->Data = NULL;
+   if (swImage->Buffer) {
+      _mesa_align_free(swImage->Buffer);
+      swImage->Buffer = NULL;
    }
 
    if (swImage->ImageOffsets) {
@@ -189,9 +189,9 @@ _swrast_map_teximage(struct gl_context *ctx,
    stride = _mesa_format_row_stride(texImage->TexFormat, texImage->Width);
    _mesa_get_format_block_size(texImage->TexFormat, &bw, &bh);
 
-   assert(swImage->Data);
+   assert(swImage->Buffer);
 
-   map = swImage->Data;
+   map = swImage->Buffer;
 
    if (texImage->TexObject->Target == GL_TEXTURE_3D ||
        texImage->TexObject->Target == GL_TEXTURE_2D_ARRAY) {
@@ -224,3 +224,138 @@ _swrast_unmap_teximage(struct gl_context *ctx,
 {
    /* nop */
 }
+
+
+void
+_swrast_map_texture(struct gl_context *ctx, struct gl_texture_object *texObj)
+{
+   const GLuint faces = texObj->Target == GL_TEXTURE_CUBE_MAP ? 6 : 1;
+   GLuint face, level;
+
+   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);
+
+            /* XXX we'll eventually call _swrast_map_teximage() here */
+            swImage->Data = swImage->Buffer;
+            assert(swImage->Buffer);
+         }
+      }
+   }
+}
+
+
+void
+_swrast_unmap_texture(struct gl_context *ctx, struct gl_texture_object *texObj)
+{
+   const GLuint faces = texObj->Target == GL_TEXTURE_CUBE_MAP ? 6 : 1;
+   GLuint face, level;
+
+   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);
+
+            /* XXX we'll eventually call _swrast_unmap_teximage() here */
+            swImage->Data = NULL;
+         }
+      }
+   }
+}
+
+
+/**
+ * Map all textures for reading prior to software rendering.
+ */
+void
+_swrast_map_textures(struct gl_context *ctx)
+{
+   GLbitfield enabledUnits = ctx->Texture._EnabledUnits;
+
+   /* loop over enabled texture units */
+   while (enabledUnits) {
+      GLuint unit = ffs(enabledUnits) - 1;
+      struct gl_texture_object *texObj = ctx->Texture.Unit[unit]._Current;
+      
+      _swrast_map_texture(ctx, texObj);
+
+      enabledUnits &= ~(1 << unit);
+   }
+}
+
+
+/**
+ * Unmap all textures for reading prior to software rendering.
+ */
+void
+_swrast_unmap_textures(struct gl_context *ctx)
+{
+   GLbitfield enabledUnits = ctx->Texture._EnabledUnits;
+
+   /* loop over enabled texture units */
+   while (enabledUnits) {
+      GLuint unit = ffs(enabledUnits) - 1;
+      struct gl_texture_object *texObj = ctx->Texture.Unit[unit]._Current;
+      
+      _swrast_unmap_texture(ctx, texObj);
+
+      enabledUnits &= ~(1 << unit);
+   }
+}
+
+
+/**
+ * Map or unmap any textures that we may be rendering to as renderbuffers.
+ */
+static void
+map_unmap_renderbuffers(struct gl_context *ctx,
+                        struct gl_framebuffer *fb,
+                        GLboolean map)
+{
+   GLuint i;
+
+   for (i = 0; i < Elements(fb->Attachment); i++) {
+      struct gl_texture_object *texObj = fb->Attachment[i].Texture;
+      if (texObj) {
+         const GLuint level = fb->Attachment[i].TextureLevel;
+         const GLuint face = fb->Attachment[i].CubeMapFace;
+         struct gl_texture_image *texImage = texObj->Image[face][level];
+         if (texImage) {
+            struct swrast_texture_image *swImage
+               = swrast_texture_image(texImage);
+
+            if (map) {
+               /* XXX we'll eventually call _swrast_map_teximage() here */
+               swImage->Data = swImage->Buffer;
+            }
+            else {
+               /* XXX we'll eventually call _swrast_unmap_teximage() here */
+               swImage->Data = NULL;
+            }
+         }
+      }
+   }
+}
+
+
+void
+_swrast_map_renderbuffers(struct gl_context *ctx)
+{
+   map_unmap_renderbuffers(ctx, ctx->DrawBuffer, GL_TRUE);
+   if (ctx->ReadBuffer != ctx->DrawBuffer)
+      map_unmap_renderbuffers(ctx, ctx->ReadBuffer, GL_TRUE);
+}
+
+
+void
+_swrast_unmap_renderbuffers(struct gl_context *ctx)
+{
+   map_unmap_renderbuffers(ctx, ctx->DrawBuffer, GL_FALSE);
+   if (ctx->ReadBuffer != ctx->DrawBuffer)
+      map_unmap_renderbuffers(ctx, ctx->ReadBuffer, GL_FALSE);
+}