mesa: Update gl_scissor_attrib to support ARB_viewport_array

Update Mesa and drivers to access updated gl_scissor_attrib.
Now have an enable bitfield and array of gl_scissor_rects.
Drivers have been updated to the new scissor enable state
attribute (gl_context.scissor.EnableFlags) but still treat it
as a single boolean which is okay as mesa will only use
bit 0 when communicating with a driver that does not support
ARB_viewport_array.

v2 (idr): Rebase fixes.

v3 (idr): Small code formatting fix suggsted by Ken.

Signed-off-by: Courtney Goeltzenleuchter <[email protected]>
Signed-off-by: Ian Romanick <[email protected]>
Reviewed-by: Kenneth Graunke <[email protected]>

7 files changed, 78 insertions, 40 deletions

diff --git a/src/mesa/main/attrib.c b/src/mesa/main/attrib.c
index 30c815d67f0..f571f9fc7f0 100644
--- a/src/mesa/main/attrib.c
+++ b/src/mesa/main/attrib.c
@@ -112,7 +112,7 @@ struct gl_enable_attrib
    GLboolean PolygonSmooth;
    GLboolean PolygonStipple;
    GLboolean RescaleNormals;
-   GLboolean Scissor;
+   GLbitfield Scissor;
    GLboolean Stencil;
    GLboolean StencilTwoSide;          /* GL_EXT_stencil_two_side */
    GLboolean MultisampleEnabled;      /* GL_ARB_multisample */
@@ -354,7 +354,7 @@ _mesa_PushAttrib(GLbitfield mask)
       attr->PolygonSmooth = ctx->Polygon.SmoothFlag;
       attr->PolygonStipple = ctx->Polygon.StippleFlag;
       attr->RescaleNormals = ctx->Transform.RescaleNormals;
-      attr->Scissor = ctx->Scissor.Enabled;
+      attr->Scissor = ctx->Scissor.EnableFlags;
       attr->Stencil = ctx->Stencil.Enabled;
       attr->StencilTwoSide = ctx->Stencil.TestTwoSide;
       attr->MultisampleEnabled = ctx->Multisample.Enabled;
@@ -658,7 +658,13 @@ pop_enable_group(struct gl_context *ctx, const struct gl_enable_attrib *enable)
                    GL_POLYGON_SMOOTH);
    TEST_AND_UPDATE(ctx->Polygon.StippleFlag, enable->PolygonStipple,
                    GL_POLYGON_STIPPLE);
-   TEST_AND_UPDATE(ctx->Scissor.Enabled, enable->Scissor, GL_SCISSOR_TEST);
+   if (ctx->Scissor.EnableFlags != enable->Scissor) {
+      unsigned i;
+
+      for (i = 0; i < ctx->Const.MaxViewports; i++) {
+         _mesa_set_enablei(ctx, GL_SCISSOR_TEST, i, (enable->Scissor >> i) & 1);
+      }
+   }
    TEST_AND_UPDATE(ctx->Stencil.Enabled, enable->Stencil, GL_STENCIL_TEST);
    if (ctx->Extensions.EXT_stencil_two_side) {
       TEST_AND_UPDATE(ctx->Stencil.TestTwoSide, enable->StencilTwoSide, GL_STENCIL_TEST_TWO_SIDE_EXT);
@@ -1264,9 +1270,13 @@ _mesa_PopAttrib(void)
             {
                const struct gl_scissor_attrib *scissor;
                scissor = (const struct gl_scissor_attrib *) attr->data;
-               _mesa_Scissor(scissor->X, scissor->Y,
-                             scissor->Width, scissor->Height);
-               _mesa_set_enable(ctx, GL_SCISSOR_TEST, scissor->Enabled);
+               _mesa_set_scissor(ctx,
+                                 scissor->ScissorArray[0].X,
+                                 scissor->ScissorArray[0].Y,
+                                 scissor->ScissorArray[0].Width,
+                                 scissor->ScissorArray[0].Height);
+               _mesa_set_enable(ctx, GL_SCISSOR_TEST, scissor->EnableFlags & 1);
+
             }
             break;
          case GL_STENCIL_BUFFER_BIT:
diff --git a/src/mesa/main/enable.c b/src/mesa/main/enable.c
index fca306890e5..a6246905e51 100644
--- a/src/mesa/main/enable.c
+++ b/src/mesa/main/enable.c
@@ -659,10 +659,15 @@ _mesa_set_enable(struct gl_context *ctx, GLenum cap, GLboolean state)
          ctx->Transform.RescaleNormals = state;
          break;
       case GL_SCISSOR_TEST:
-         if (ctx->Scissor.Enabled == state)
-            return;
-         FLUSH_VERTICES(ctx, _NEW_SCISSOR);
-         ctx->Scissor.Enabled = state;
+         {
+            /* Must expand glEnable to all scissors */
+            GLbitfield newEnabled =
+               state * ((1 << ctx->Const.MaxViewports) - 1);
+            if (newEnabled != ctx->Scissor.EnableFlags) {
+               FLUSH_VERTICES(ctx, _NEW_SCISSOR);
+               ctx->Scissor.EnableFlags = newEnabled;
+            }
+         }
          break;
       case GL_STENCIL_TEST:
          if (ctx->Stencil.Enabled == state)
@@ -1076,6 +1081,20 @@ _mesa_set_enablei(struct gl_context *ctx, GLenum cap,
             ctx->Color.BlendEnabled &= ~(1 << index);
       }
       break;
+   case GL_SCISSOR_TEST:
+      if (index >= ctx->Const.MaxViewports) {
+         _mesa_error(ctx, GL_INVALID_VALUE, "%s(index=%u)",
+                     state ? "glEnablei" : "glDisablei", index);
+         return;
+      }
+      if (((ctx->Scissor.EnableFlags >> index) & 1) != state) {
+         FLUSH_VERTICES(ctx, _NEW_SCISSOR);
+         if (state)
+            ctx->Scissor.EnableFlags |= (1 << index);
+         else
+            ctx->Scissor.EnableFlags &= ~(1 << index);
+      }
+      break;
    default:
       goto invalid_enum_error;
    }
@@ -1349,7 +1368,7 @@ _mesa_IsEnabled( GLenum cap )
             goto invalid_enum_error;
          return ctx->Transform.RescaleNormals;
       case GL_SCISSOR_TEST:
-	 return ctx->Scissor.Enabled;
+	 return ctx->Scissor.EnableFlags & 1;  /* return state for index 0 */
       case GL_STENCIL_TEST:
 	 return ctx->Stencil.Enabled;
       case GL_TEXTURE_1D:
diff --git a/src/mesa/main/framebuffer.c b/src/mesa/main/framebuffer.c
index 2fad4588066..f14f7a4877e 100644
--- a/src/mesa/main/framebuffer.c
+++ b/src/mesa/main/framebuffer.c
@@ -380,18 +380,19 @@ _mesa_update_draw_buffer_bounds(struct gl_context *ctx)
    buffer->_Xmax = buffer->Width;
    buffer->_Ymax = buffer->Height;
 
-   if (ctx->Scissor.Enabled) {
-      if (ctx->Scissor.X > buffer->_Xmin) {
-	 buffer->_Xmin = ctx->Scissor.X;
+   /* Default to the first scissor as that's always valid */
+   if (ctx->Scissor.EnableFlags & 1) {
+      if (ctx->Scissor.ScissorArray[0].X > buffer->_Xmin) {
+	 buffer->_Xmin = ctx->Scissor.ScissorArray[0].X;
       }
-      if (ctx->Scissor.Y > buffer->_Ymin) {
-	 buffer->_Ymin = ctx->Scissor.Y;
+      if (ctx->Scissor.ScissorArray[0].Y > buffer->_Ymin) {
+	 buffer->_Ymin = ctx->Scissor.ScissorArray[0].Y;
       }
-      if (ctx->Scissor.X + ctx->Scissor.Width < buffer->_Xmax) {
-	 buffer->_Xmax = ctx->Scissor.X + ctx->Scissor.Width;
+      if (ctx->Scissor.ScissorArray[0].X + ctx->Scissor.ScissorArray[0].Width < buffer->_Xmax) {
+	 buffer->_Xmax = ctx->Scissor.ScissorArray[0].X + ctx->Scissor.ScissorArray[0].Width;
       }
-      if (ctx->Scissor.Y + ctx->Scissor.Height < buffer->_Ymax) {
-	 buffer->_Ymax = ctx->Scissor.Y + ctx->Scissor.Height;
+      if (ctx->Scissor.ScissorArray[0].Y + ctx->Scissor.ScissorArray[0].Height < buffer->_Ymax) {
+	 buffer->_Ymax = ctx->Scissor.ScissorArray[0].Y + ctx->Scissor.ScissorArray[0].Height;
       }
       /* finally, check for empty region */
       if (buffer->_Xmin > buffer->_Xmax) {
diff --git a/src/mesa/main/get.c b/src/mesa/main/get.c
index b13f9a3dba6..dd6ac311674 100644
--- a/src/mesa/main/get.c
+++ b/src/mesa/main/get.c
@@ -665,10 +665,14 @@ find_custom_value(struct gl_context *ctx, const struct value_desc *d, union valu
       break;
 
    case GL_SCISSOR_BOX:
-      v->value_int_4[0] = ctx->Scissor.X;
-      v->value_int_4[1] = ctx->Scissor.Y;
-      v->value_int_4[2] = ctx->Scissor.Width;
-      v->value_int_4[3] = ctx->Scissor.Height;
+      v->value_int_4[0] = ctx->Scissor.ScissorArray[0].X;
+      v->value_int_4[1] = ctx->Scissor.ScissorArray[0].Y;
+      v->value_int_4[2] = ctx->Scissor.ScissorArray[0].Width;
+      v->value_int_4[3] = ctx->Scissor.ScissorArray[0].Height;
+      break;
+
+   case GL_SCISSOR_TEST:
+      v->value_bool = ctx->Scissor.EnableFlags & 1;
       break;
 
    case GL_LIST_INDEX:
diff --git a/src/mesa/main/get_hash_params.py b/src/mesa/main/get_hash_params.py
index bc2bbafa8c3..6fcd4f622cd 100644
--- a/src/mesa/main/get_hash_params.py
+++ b/src/mesa/main/get_hash_params.py
@@ -30,7 +30,7 @@ descriptor=[
   [ "POLYGON_OFFSET_FILL", "CONTEXT_BOOL(Polygon.OffsetFill), NO_EXTRA" ],
   [ "RED_BITS", "BUFFER_INT(Visual.redBits), extra_new_buffers" ],
   [ "SCISSOR_BOX", "LOC_CUSTOM, TYPE_INT_4, 0, NO_EXTRA" ],
-  [ "SCISSOR_TEST", "CONTEXT_BOOL(Scissor.Enabled), NO_EXTRA" ],
+  [ "SCISSOR_TEST", "LOC_CUSTOM, TYPE_BOOLEAN, NO_OFFSET, NO_EXTRA" ],
   [ "STENCIL_BITS", "BUFFER_INT(Visual.stencilBits), extra_new_buffers" ],
   [ "STENCIL_CLEAR_VALUE", "CONTEXT_INT(Stencil.Clear), NO_EXTRA" ],
   [ "STENCIL_FAIL", "LOC_CUSTOM, TYPE_ENUM, NO_OFFSET, NO_EXTRA" ],
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index a939d9c9f62..9dbfa6bfbc6 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -1009,12 +1009,16 @@ struct gl_polygon_attrib
 /**
  * Scissor attributes (GL_SCISSOR_BIT).
  */
-struct gl_scissor_attrib
+struct gl_scissor_rect
 {
-   GLboolean Enabled;		/**< Scissor test enabled? */
    GLint X, Y;			/**< Lower left corner of box */
    GLsizei Width, Height;	/**< Size of box */
 };
+struct gl_scissor_attrib
+{
+   GLbitfield EnableFlags;	/**< Scissor test enabled? */
+   struct gl_scissor_rect ScissorArray[MAX_VIEWPORTS];
+};
 
 
 /**
diff --git a/src/mesa/main/scissor.c b/src/mesa/main/scissor.c
index ac86bd59138..7ec927ecd8b 100644
--- a/src/mesa/main/scissor.c
+++ b/src/mesa/main/scissor.c
@@ -66,17 +66,17 @@ void
 _mesa_set_scissor(struct gl_context *ctx, 
                   GLint x, GLint y, GLsizei width, GLsizei height)
 {
-   if (x == ctx->Scissor.X &&
-       y == ctx->Scissor.Y &&
-       width == ctx->Scissor.Width &&
-       height == ctx->Scissor.Height)
+   if (x == ctx->Scissor.ScissorArray[0].X &&
+       y == ctx->Scissor.ScissorArray[0].Y &&
+       width == ctx->Scissor.ScissorArray[0].Width &&
+       height == ctx->Scissor.ScissorArray[0].Height)
       return;
 
    FLUSH_VERTICES(ctx, _NEW_SCISSOR);
-   ctx->Scissor.X = x;
-   ctx->Scissor.Y = y;
-   ctx->Scissor.Width = width;
-   ctx->Scissor.Height = height;
+   ctx->Scissor.ScissorArray[0].X = x;
+   ctx->Scissor.ScissorArray[0].Y = y;
+   ctx->Scissor.ScissorArray[0].Width = width;
+   ctx->Scissor.ScissorArray[0].Height = height;
 
    if (ctx->Driver.Scissor)
       ctx->Driver.Scissor(ctx);
@@ -91,9 +91,9 @@ void
 _mesa_init_scissor(struct gl_context *ctx)
 {
    /* Scissor group */
-   ctx->Scissor.Enabled = GL_FALSE;
-   ctx->Scissor.X = 0;
-   ctx->Scissor.Y = 0;
-   ctx->Scissor.Width = 0;
-   ctx->Scissor.Height = 0;
+   ctx->Scissor.EnableFlags = GL_FALSE;
+   ctx->Scissor.ScissorArray[0].X = 0;
+   ctx->Scissor.ScissorArray[0].Y = 0;
+   ctx->Scissor.ScissorArray[0].Width = 0;
+   ctx->Scissor.ScissorArray[0].Height = 0;
 }