Mesa (master): mesa: add num_buffers() helper in blend.c

[Brian Paul]

Module: Mesa
Branch: master
Commit: d8c23d156d9b014a52d83d1a2eb051981b5203f3
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=d8c23d156d9b014a52d83d1a2eb051981b5203f3

Author: Brian Paul <brianp at vmware.com>
Date:   Wed Oct 14 09:53:26 2015 -0600

mesa: add num_buffers() helper in blend.c

Reviewed-by: Eric Anholt <eric at anholt.net>

---

 src/mesa/main/blend.c |   37 ++++++++++++++++++++++---------------
 1 file changed, 22 insertions(+), 15 deletions(-)

diff --git a/src/mesa/main/blend.c b/src/mesa/main/blend.c
index 9dec2d4..20aa498 100644
--- a/src/mesa/main/blend.c
+++ b/src/mesa/main/blend.c
@@ -190,6 +190,19 @@ update_uses_dual_src(struct gl_context *ctx, int buf)
        blend_factor_is_dual_src(ctx->Color.Blend[buf].DstA));
 }
 
+
+/**
+ * Return the number of per-buffer blend states to update in
+ * glBlendFunc, glBlendFuncSeparate, glBlendEquation, etc.
+ */
+static inline unsigned
+num_buffers(const struct gl_context *ctx)
+{
+   return ctx->Extensions.ARB_draw_buffers_blend
+      ? ctx->Const.MaxDrawBuffers : 1;
+}
+
+
 /**
  * Set the separate blend source/dest factors for all draw buffers.
  *
@@ -202,9 +215,10 @@ void GLAPIENTRY
 _mesa_BlendFuncSeparate( GLenum sfactorRGB, GLenum dfactorRGB,
                             GLenum sfactorA, GLenum dfactorA )
 {
-   GLuint buf, numBuffers;
-   bool changed = false;
    GET_CURRENT_CONTEXT(ctx);
+   const unsigned numBuffers = num_buffers(ctx);
+   unsigned buf;
+   bool changed = false;
 
    if (MESA_VERBOSE & VERBOSE_API)
       _mesa_debug(ctx, "glBlendFuncSeparate %s %s %s %s\n",
@@ -213,9 +227,6 @@ _mesa_BlendFuncSeparate( GLenum sfactorRGB, GLenum dfactorRGB,
                   _mesa_enum_to_string(sfactorA),
                   _mesa_enum_to_string(dfactorA));
 
-   numBuffers = ctx->Extensions.ARB_draw_buffers_blend
-      ? ctx->Const.MaxDrawBuffers : 1;
-
    /* Check if we're really changing any state.  If not, return early. */
    if (ctx->Color._BlendFuncPerBuffer) {
       /* Check all per-buffer states */
@@ -349,17 +360,15 @@ legal_blend_equation(const struct gl_context *ctx, GLenum mode)
 void GLAPIENTRY
 _mesa_BlendEquation( GLenum mode )
 {
-   GLuint buf, numBuffers;
-   bool changed = false;
    GET_CURRENT_CONTEXT(ctx);
+   const unsigned numBuffers = num_buffers(ctx);
+   unsigned buf;
+   bool changed = false;
 
    if (MESA_VERBOSE & VERBOSE_API)
       _mesa_debug(ctx, "glBlendEquation(%s)\n",
                   _mesa_enum_to_string(mode));
 
-   numBuffers = ctx->Extensions.ARB_draw_buffers_blend
-      ? ctx->Const.MaxDrawBuffers : 1;
-
    if (ctx->Color._BlendEquationPerBuffer) {
       /* Check all per-buffer states */
       for (buf = 0; buf < numBuffers; buf++) {
@@ -436,18 +445,16 @@ _mesa_BlendEquationiARB(GLuint buf, GLenum mode)
 void GLAPIENTRY
 _mesa_BlendEquationSeparate( GLenum modeRGB, GLenum modeA )
 {
-   GLuint buf, numBuffers;
-   bool changed = false;
    GET_CURRENT_CONTEXT(ctx);
+   const unsigned numBuffers = num_buffers(ctx);
+   unsigned buf;
+   bool changed = false;
 
    if (MESA_VERBOSE & VERBOSE_API)
       _mesa_debug(ctx, "glBlendEquationSeparateEXT(%s %s)\n",
                   _mesa_enum_to_string(modeRGB),
                   _mesa_enum_to_string(modeA));
 
-   numBuffers = ctx->Extensions.ARB_draw_buffers_blend
-      ? ctx->Const.MaxDrawBuffers : 1;
-
    if (ctx->Color._BlendEquationPerBuffer) {
       /* Check all per-buffer states */
       for (buf = 0; buf < numBuffers; buf++) {