[Mesa-dev] [PATCH 23/37] mesa: Add new scissor entry points for GL_ARB_viewport_array

[Ian Romanick]

From: Courtney Goeltzenleuchter <courtney at LunarG.com>

v2 (idr): Use set_scissor_no_notify (and manually notify the driver)
instead of calling _mesa_set_scissori.  Refactory bodies of
_mesa_ScissorIndexed and _mesa_ScissorIndexedv into a shared function.
Perform parameter validation in the same order in all three functions.
Pull MaxViewports comparison fix (in _mesa_ScissorArrayv) from the next
patch to this patch.

Signed-off-by: Courtney Goeltzenleuchter <courtney at LunarG.com>
Signed-off-by: Ian Romanick <ian.d.romanick at intel.com>
Reviewed-by: Kenneth Graunke <kenneth at whitecape.org>
---
 src/mesa/main/scissor.c | 93 +++++++++++++++++++++++++++++++++++++++++++++++++
 src/mesa/main/scissor.h |  8 +++++
 2 files changed, 101 insertions(+)

diff --git a/src/mesa/main/scissor.c b/src/mesa/main/scissor.c
index 9caac2e..14c8e8a 100644
--- a/src/mesa/main/scissor.c
+++ b/src/mesa/main/scissor.c
@@ -114,6 +114,99 @@ _mesa_set_scissor(struct gl_context *ctx, unsigned idx,
       ctx->Driver.Scissor(ctx);
 }
 
+/**
+ * Define count scissor boxes starting at index.
+ *
+ * \param index  index of first scissor records to set
+ * \param count  number of scissor records to set
+ * \param x, y   pointer to array of struct gl_scissor_rects
+ *
+ * \sa glScissorArrayv().
+ *
+ * Verifies the parameters and call set_scissor_no_notify to do the work.
+ */
+void GLAPIENTRY
+_mesa_ScissorArrayv(GLuint first, GLsizei count, const GLint *v)
+{
+   int i;
+   struct gl_scissor_rect *p = (struct gl_scissor_rect *) v;
+   GET_CURRENT_CONTEXT(ctx);
+
+   if ((first + count) > ctx->Const.MaxViewports) {
+      _mesa_error(ctx, GL_INVALID_VALUE,
+                  "glScissorArrayv: first (%d) + count (%d) >= MaxViewports (%d)",
+                  first, count, ctx->Const.MaxViewports);
+      return;
+   }
+
+   /* Verify width & height */
+   for (i = 0; i < count; i++) {
+      if (p[i].Width < 0 || p[i].Height < 0) {
+         _mesa_error(ctx, GL_INVALID_VALUE,
+                     "glScissorArrayv: index (%d) width or height < 0 (%d, %d)",
+                     i, p[i].Width, p[i].Height);
+      }
+   }
+
+   for (i = 0; i < count; i++)
+      set_scissor_no_notify(ctx, i + first,
+                            p[i].X, p[i].Y, p[i].Width, p[i].Height);
+
+   if (ctx->Driver.Scissor)
+      ctx->Driver.Scissor(ctx);
+}
+
+/**
+ * Define the scissor box.
+ *
+ * \param index  index of scissor records to set
+ * \param x, y   coordinates of the scissor box lower-left corner.
+ * \param width  width of the scissor box.
+ * \param height height of the scissor box.
+ *
+ * Verifies the parameters call set_scissor_no_notify to do the work.
+ */
+static void
+ScissorIndexed(GLuint index, GLint left, GLint bottom,
+               GLsizei width, GLsizei height, const char *function)
+{
+   GET_CURRENT_CONTEXT(ctx);
+
+   if (MESA_VERBOSE & VERBOSE_API)
+      _mesa_debug(ctx, "%s(%d, %d, %d, %d, %d)\n",
+                  function, index, left, bottom, width, height);
+
+   if (index >= ctx->Const.MaxViewports) {
+      _mesa_error(ctx, GL_INVALID_VALUE,
+                  "%s: index (%d) >= MaxViewports (%d)",
+                  function, index, ctx->Const.MaxViewports);
+      return;
+   }
+
+   if (width < 0 || height < 0) {
+      _mesa_error(ctx, GL_INVALID_VALUE,
+                  "%s: index (%d) width or height < 0 (%d, %d)",
+                  function, index, width, height);
+   }
+
+   set_scissor_no_notify(ctx, index, left, bottom, width, height);
+
+   if (ctx->Driver.Scissor)
+      ctx->Driver.Scissor(ctx);
+}
+
+void GLAPIENTRY
+_mesa_ScissorIndexed(GLuint index, GLint left, GLint bottom,
+                     GLsizei width, GLsizei height)
+{
+   ScissorIndexed(index, left, bottom, width, height, "glScissorIndexd");
+}
+
+void GLAPIENTRY
+_mesa_ScissorIndexedv(GLuint index, const GLint *v)
+{
+   ScissorIndexed(index, v[0], v[1], v[2], v[3], "glScissorIndexdv");
+}
 
 /**
  * Initialize the context's scissor state.
diff --git a/src/mesa/main/scissor.h b/src/mesa/main/scissor.h
index 5726a00..5f9a994 100644
--- a/src/mesa/main/scissor.h
+++ b/src/mesa/main/scissor.h
@@ -34,6 +34,14 @@ struct gl_context;
 extern void GLAPIENTRY
 _mesa_Scissor( GLint x, GLint y, GLsizei width, GLsizei height );
 
+extern void GLAPIENTRY
+_mesa_ScissorArrayv(GLuint first, GLsizei count, const GLint * v);
+
+extern void GLAPIENTRY
+_mesa_ScissorIndexed(GLuint index, GLint left, GLint bottom, GLsizei width, GLsizei height);
+
+extern void GLAPIENTRY
+_mesa_ScissorIndexedv(GLuint index, const GLint * v);
 
 extern void
 _mesa_set_scissor(struct gl_context *ctx, unsigned idx,
-- 
1.8.1.4