mesa: rename MaxTransformFeedbackSeparateAttribs to MaxTransformFeedbackBuffers

This is a cleanup for ARB_transform_feedback3, where
GL_MAX_TRANSFORM_FEEDBACK_BUFFERS is introduced for interleaved attribs and
has the same meaning as GL_MAX_.._SEPARATE_ATTRIBS for separate attribs.

Also, the maximum number of TFB buffers is reduced from 32 to 4, which makes
this patch useful even without the extension.
I don't know of any hardware which can do more than 4.

Reviewed-by: Brian Paul <brianp@vmware.com>

src/mesa/drivers/dri/i965/brw_context.c

@@ -138,7 +138,7 @@ brwCreateContext(int api,
     * So we need to override the Mesa default (which is based only on software
     * limits).
     */
-   ctx->Const.MaxTransformFeedbackSeparateAttribs = BRW_MAX_SOL_BUFFERS;
+   ctx->Const.MaxTransformFeedbackBuffers = BRW_MAX_SOL_BUFFERS;
 
    /* On Gen6, in the worst case, we use up one binding table entry per
     * transform feedback component (see comments above the definition of

src/mesa/main/bufferobj.c

@@ -869,7 +869,7 @@ _mesa_DeleteBuffersARB(GLsizei n, const GLuint *ids)
          if (ctx->TransformFeedback.CurrentBuffer == bufObj) {
             _mesa_BindBufferARB( GL_TRANSFORM_FEEDBACK_BUFFER, 0 );
          }
-         for (j = 0; j < MAX_FEEDBACK_ATTRIBS; j++) {
+         for (j = 0; j < MAX_FEEDBACK_BUFFERS; j++) {
             if (ctx->TransformFeedback.CurrentObject->Buffers[j] == bufObj) {
                _mesa_BindBufferBase( GL_TRANSFORM_FEEDBACK_BUFFER, j, 0 );
             }

src/mesa/main/config.h

@@ -249,6 +249,7 @@
 #define SUPPORTED_ATI_BUMP_UNITS 0xff
 
 /** For GL_EXT_transform_feedback */
+#define MAX_FEEDBACK_BUFFERS 4
 #define MAX_FEEDBACK_ATTRIBS 32
 
 /** For GL_ARB_geometry_shader4 */

src/mesa/main/context.c

@@ -652,7 +652,7 @@ _mesa_init_constants(struct gl_context *ctx)
    ctx->Const.QuadsFollowProvokingVertexConvention = GL_TRUE;
 
    /* GL_EXT_transform_feedback */
-   ctx->Const.MaxTransformFeedbackSeparateAttribs = MAX_FEEDBACK_ATTRIBS;
+   ctx->Const.MaxTransformFeedbackBuffers = MAX_FEEDBACK_BUFFERS;
    ctx->Const.MaxTransformFeedbackSeparateComponents = 4 * MAX_FEEDBACK_ATTRIBS;
    ctx->Const.MaxTransformFeedbackInterleavedComponents = 4 * MAX_FEEDBACK_ATTRIBS;
 

src/mesa/main/get.c

@@ -1232,7 +1232,7 @@ static const struct value_desc values[] = {
      CONTEXT_INT(Const.MaxTransformFeedbackInterleavedComponents),
      extra_EXT_transform_feedback },
    { GL_MAX_TRANSFORM_FEEDBACK_SEPARATE_ATTRIBS,
-     CONTEXT_INT(Const.MaxTransformFeedbackSeparateAttribs),
+     CONTEXT_INT(Const.MaxTransformFeedbackBuffers),
      extra_EXT_transform_feedback },
    { GL_MAX_TRANSFORM_FEEDBACK_SEPARATE_COMPONENTS,
      CONTEXT_INT(Const.MaxTransformFeedbackSeparateComponents),
@@ -2544,7 +2544,7 @@ find_value_indexed(const char *func, GLenum pname, int index, union value *v)
       return TYPE_INT_4;
 
    case GL_TRANSFORM_FEEDBACK_BUFFER_START:
-      if (index >= ctx->Const.MaxTransformFeedbackSeparateAttribs)
+      if (index >= ctx->Const.MaxTransformFeedbackBuffers)
 	 goto invalid_value;
       if (!ctx->Extensions.EXT_transform_feedback)
 	 goto invalid_enum;
@@ -2552,7 +2552,7 @@ find_value_indexed(const char *func, GLenum pname, int index, union value *v)
       return TYPE_INT64;
 
    case GL_TRANSFORM_FEEDBACK_BUFFER_SIZE:
-      if (index >= ctx->Const.MaxTransformFeedbackSeparateAttribs)
+      if (index >= ctx->Const.MaxTransformFeedbackBuffers)
 	 goto invalid_value;
       if (!ctx->Extensions.EXT_transform_feedback)
 	 goto invalid_enum;
@@ -2560,7 +2560,7 @@ find_value_indexed(const char *func, GLenum pname, int index, union value *v)
       return TYPE_INT64;
 
    case GL_TRANSFORM_FEEDBACK_BUFFER_BINDING:
-      if (index >= ctx->Const.MaxTransformFeedbackSeparateAttribs)
+      if (index >= ctx->Const.MaxTransformFeedbackBuffers)
 	 goto invalid_value;
       if (!ctx->Extensions.EXT_transform_feedback)
 	 goto invalid_enum;

src/mesa/main/mtypes.h

@@ -1795,7 +1795,7 @@ struct gl_transform_feedback_info
     * hardware back-ends to determine the correct stride when interleaving
     * multiple transform feedback outputs in the same buffer.
     */
-   unsigned BufferStride[MAX_FEEDBACK_ATTRIBS];
+   unsigned BufferStride[MAX_FEEDBACK_BUFFERS];
 };
 
 
@@ -1812,13 +1812,13 @@ struct gl_transform_feedback_object
                                 at least once? */
 
    /** The feedback buffers */
-   GLuint BufferNames[MAX_FEEDBACK_ATTRIBS];
-   struct gl_buffer_object *Buffers[MAX_FEEDBACK_ATTRIBS];
+   GLuint BufferNames[MAX_FEEDBACK_BUFFERS];
+   struct gl_buffer_object *Buffers[MAX_FEEDBACK_BUFFERS];
 
    /** Start of feedback data in dest buffer */
-   GLintptr Offset[MAX_FEEDBACK_ATTRIBS];
+   GLintptr Offset[MAX_FEEDBACK_BUFFERS];
    /** Max data to put into dest buffer (in bytes) */
-   GLsizeiptr Size[MAX_FEEDBACK_ATTRIBS];
+   GLsizeiptr Size[MAX_FEEDBACK_BUFFERS];
 };
 
 
@@ -2834,7 +2834,7 @@ struct gl_constants
    GLbitfield ProfileMask;   /**< Mask of CONTEXT_x_PROFILE_BIT */
 
    /** GL_EXT_transform_feedback */
-   GLuint MaxTransformFeedbackSeparateAttribs;
+   GLuint MaxTransformFeedbackBuffers;
    GLuint MaxTransformFeedbackSeparateComponents;
    GLuint MaxTransformFeedbackInterleavedComponents;
 

src/mesa/main/transformfeedback.c

@@ -447,7 +447,7 @@ _mesa_bind_buffer_range_transform_feedback(struct gl_context *ctx,
       return;
    }
 
-   if (index >= ctx->Const.MaxTransformFeedbackSeparateAttribs) {
+   if (index >= ctx->Const.MaxTransformFeedbackBuffers) {
       _mesa_error(ctx, GL_INVALID_VALUE, "glBindBufferRange(index=%d)", index);
       return;
    }
@@ -490,7 +490,7 @@ _mesa_bind_buffer_base_transform_feedback(struct gl_context *ctx,
       return;
    }
 
-   if (index >= ctx->Const.MaxTransformFeedbackSeparateAttribs) {
+   if (index >= ctx->Const.MaxTransformFeedbackBuffers) {
       _mesa_error(ctx, GL_INVALID_VALUE, "glBindBufferBase(index=%d)", index);
       return;
    }
@@ -531,7 +531,7 @@ _mesa_BindBufferOffsetEXT(GLenum target, GLuint index, GLuint buffer,
       return;
    }
 
-   if (index >= ctx->Const.MaxTransformFeedbackSeparateAttribs) {
+   if (index >= ctx->Const.MaxTransformFeedbackBuffers) {
       _mesa_error(ctx, GL_INVALID_VALUE,
                   "glBindBufferOffsetEXT(index=%d)", index);
       return;
@@ -590,7 +590,7 @@ _mesa_TransformFeedbackVaryings(GLuint program, GLsizei count,
 
    if (count < 0 ||
        (bufferMode == GL_SEPARATE_ATTRIBS &&
-        (GLuint) count > ctx->Const.MaxTransformFeedbackSeparateAttribs)) {
+        (GLuint) count > ctx->Const.MaxTransformFeedbackBuffers)) {
       _mesa_error(ctx, GL_INVALID_VALUE,
                   "glTransformFeedbackVaryings(count=%d)", count);
       return;

src/mesa/state_tracker/st_extensions.c

@@ -236,8 +236,9 @@ void st_init_limits(struct st_context *st)
 
    c->UniformBooleanTrue = ~0;
 
-   c->MaxTransformFeedbackSeparateAttribs =
+   c->MaxTransformFeedbackBuffers =
       screen->get_param(screen, PIPE_CAP_MAX_STREAM_OUTPUT_BUFFERS);
+   c->MaxTransformFeedbackBuffers = MIN2(c->MaxTransformFeedbackBuffers, MAX_FEEDBACK_BUFFERS);
    c->MaxTransformFeedbackSeparateComponents =
       screen->get_param(screen, PIPE_CAP_MAX_STREAM_OUTPUT_SEPARATE_COMPONENTS);
    c->MaxTransformFeedbackInterleavedComponents =