diff options
Diffstat (limited to 'src/mesa/main/buffers.c')
| -rw-r--r-- | src/mesa/main/buffers.c | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/src/mesa/main/buffers.c b/src/mesa/main/buffers.c index 818d068a12b..c5f13345f04 100644 --- a/src/mesa/main/buffers.c +++ b/src/mesa/main/buffers.c @@ -120,11 +120,9 @@ draw_buffer_enum_to_bitmask(GLenum buffer) 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: @@ -177,11 +175,9 @@ read_buffer_enum_to_index(GLenum buffer) 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: @@ -290,7 +286,10 @@ _mesa_DrawBuffersARB(GLsizei n, const GLenum *buffers) GET_CURRENT_CONTEXT(ctx); ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); - 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; } @@ -332,12 +331,14 @@ _mesa_DrawBuffersARB(GLsizei n, const GLenum *buffers) _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); } |