case GL_AUX0:
return BUFFER_BIT_AUX0;
case GL_AUX1:
- return BUFFER_BIT_AUX1;
case GL_AUX2:
- return BUFFER_BIT_AUX2;
case GL_AUX3:
- return BUFFER_BIT_AUX3;
+ return 1 << BUFFER_COUNT; /* invalid, but not BAD_MASK */
case GL_COLOR_ATTACHMENT0_EXT:
return BUFFER_BIT_COLOR0;
case GL_COLOR_ATTACHMENT1_EXT:
case GL_AUX0:
return BUFFER_AUX0;
case GL_AUX1:
- return BUFFER_AUX1;
case GL_AUX2:
- return BUFFER_AUX2;
case GL_AUX3:
- return BUFFER_AUX3;
+ return BUFFER_COUNT; /* invalid, but not -1 */
case GL_COLOR_ATTACHMENT0_EXT:
return BUFFER_COLOR0;
case GL_COLOR_ATTACHMENT1_EXT:
destMask = draw_buffer_enum_to_bitmask(buffer);
if (destMask == BAD_MASK) {
/* totally bogus buffer */
- _mesa_error(ctx, GL_INVALID_ENUM, "glDrawBuffer(buffer)");
+ _mesa_error(ctx, GL_INVALID_ENUM, "glDrawBuffer(buffer=0x%x)", buffer);
return;
}
destMask &= supportedMask;
if (destMask == 0x0) {
/* none of the named color buffers exist! */
- _mesa_error(ctx, GL_INVALID_OPERATION, "glDrawBuffer(buffer)");
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glDrawBuffer(buffer=0x%x)", buffer);
return;
}
}
GET_CURRENT_CONTEXT(ctx);
ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
- if (!ctx->Extensions.ARB_draw_buffers) {
- _mesa_error(ctx, GL_INVALID_OPERATION, "glDrawBuffersARB");
- return;
- }
- if (n < 1 || n > (GLsizei) ctx->Const.MaxDrawBuffers) {
+ /* Turns out n==0 is a valid input that should not produce an error.
+ * The remaining code below correctly handles the n==0 case.
+ */
+ if (n < 0 || n > (GLsizei) ctx->Const.MaxDrawBuffers) {
_mesa_error(ctx, GL_INVALID_VALUE, "glDrawBuffersARB(n)");
return;
}
_mesa_drawbuffers(ctx, n, buffers, destMask);
/*
- * Call device driver function.
+ * Call device driver function. Note that n can be equal to 0,
+ * in which case we don't want to reference buffers[0], which
+ * may not be valid.
*/
if (ctx->Driver.DrawBuffers)
ctx->Driver.DrawBuffers(ctx, n, buffers);
else if (ctx->Driver.DrawBuffer)
- ctx->Driver.DrawBuffer(ctx, buffers[0]);
+ ctx->Driver.DrawBuffer(ctx, n>0? buffers[0]:GL_NONE);
}