/**
* Called by glDrawBuffer().
* Specify which renderbuffer(s) to draw into for the first color output.
* <buffer> can name zero, one, two or four renderbuffers!
* \sa _mesa_DrawBuffers
*
* \param buffer buffer token such as GL_LEFT or GL_FRONT_AND_BACK, etc.
*
* Note that the behaviour of this function depends on whether the
* current ctx->DrawBuffer is a window-system framebuffer or a user-created
* framebuffer object.
* In the former case, we update the per-context ctx->Color.DrawBuffer
* state var _and_ the FB's ColorDrawBuffer state.
* In the later case, we update the FB's ColorDrawBuffer state only.
*
* Furthermore, upon a MakeCurrent() or BindFramebuffer() call, if the
* new FB is a window system FB, we need to re-update the FB's
* ColorDrawBuffer state to match the context. This is handled in
* _mesa_update_framebuffer().
*
* See the GL_EXT_framebuffer_object spec for more info.
*/
void GLAPIENTRY
_mesa_DrawBuffer(GLenum buffer)
{
GLbitfield destMask;
GET_CURRENT_CONTEXT(ctx);
FLUSH_VERTICES(ctx, 0);
if (MESA_VERBOSE & VERBOSE_API) {
_mesa_debug(ctx, "glDrawBuffer %s\n", _mesa_lookup_enum_by_nr(buffer));
}
if (buffer == GL_NONE) {
destMask = 0x0;
}
else {
const GLbitfield supportedMask
= supported_buffer_bitmask(ctx, ctx->DrawBuffer);
destMask = draw_buffer_enum_to_bitmask(ctx, buffer);
if (destMask == BAD_MASK) {
/* totally bogus 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=0x%x)", buffer);
return;
}
}
/* if we get here, there's no error so set new state */
_mesa_drawbuffers(ctx, 1, &buffer, &destMask);
/*
* Call device driver function.
*/
if (ctx->Driver.DrawBuffers)
ctx->Driver.DrawBuffers(ctx, 1, &buffer);
else if (ctx->Driver.DrawBuffer)
ctx->Driver.DrawBuffer(ctx, buffer);
}
/**
* Called by glDrawBuffer().
* Specify which renderbuffer(s) to draw into for the first color output.
* <buffer> can name zero, one, two or four renderbuffers!
* \sa _mesa_DrawBuffers
*
* \param buffer buffer token such as GL_LEFT or GL_FRONT_AND_BACK, etc.
*
* Note that the behaviour of this function depends on whether the
* current ctx->DrawBuffer is a window-system framebuffer or a user-created
* framebuffer object.
* In the former case, we update the per-context ctx->Color.DrawBuffer
* state var _and_ the FB's ColorDrawBuffer state.
* In the later case, we update the FB's ColorDrawBuffer state only.
*
* Furthermore, upon a MakeCurrent() or BindFramebuffer() call, if the
* new FB is a window system FB, we need to re-update the FB's
* ColorDrawBuffer state to match the context. This is handled in
* _mesa_update_framebuffer().
*
* See the GL_EXT_framebuffer_object spec for more info.
*/
void
_mesa_draw_buffer(struct gl_context *ctx, struct gl_framebuffer *fb,
GLenum buffer, const char *caller)
{
GLbitfield destMask;
FLUSH_VERTICES(ctx, 0);
if (MESA_VERBOSE & VERBOSE_API) {
_mesa_debug(ctx, "%s %s\n", caller, _mesa_enum_to_string(buffer));
}
if (buffer == GL_NONE) {
destMask = 0x0;
}
else {
const GLbitfield supportedMask
= supported_buffer_bitmask(ctx, fb);
destMask = draw_buffer_enum_to_bitmask(ctx, buffer);
if (destMask == BAD_MASK) {
/* totally bogus buffer */
_mesa_error(ctx, GL_INVALID_ENUM, "%s(invalid buffer %s)", caller,
_mesa_enum_to_string(buffer));
return;
}
destMask &= supportedMask;
if (destMask == 0x0) {
/* none of the named color buffers exist! */
_mesa_error(ctx, GL_INVALID_OPERATION, "%s(invalid buffer %s)",
caller, _mesa_enum_to_string(buffer));
return;
}
}
/* if we get here, there's no error so set new state */
_mesa_drawbuffers(ctx, fb, 1, &buffer, &destMask);
/* Call device driver function only if fb is the bound draw buffer */
if (fb == ctx->DrawBuffer) {
if (ctx->Driver.DrawBuffers)
ctx->Driver.DrawBuffers(ctx, 1, &buffer);
else if (ctx->Driver.DrawBuffer)
ctx->Driver.DrawBuffer(ctx, buffer);
}
}
/**
* Helper function to set the GL_DRAW_BUFFER state in the context and
* current FBO. Called via glDrawBuffer(), glDrawBuffersARB()
*
* All error checking will have been done prior to calling this function
* so nothing should go wrong at this point.
*
* \param ctx current context
* \param n number of color outputs to set
* \param buffers array[n] of colorbuffer names, like GL_LEFT.
* \param destMask array[n] of BUFFER_BIT_* bitmasks which correspond to the
* colorbuffer names. (i.e. GL_FRONT_AND_BACK =>
* BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_BACK_LEFT).
*/
void
_mesa_drawbuffers(struct gl_context *ctx, GLuint n, const GLenum *buffers,
const GLbitfield *destMask)
{
struct gl_framebuffer *fb = ctx->DrawBuffer;
GLbitfield mask[MAX_DRAW_BUFFERS];
GLuint buf;
if (!destMask) {
/* compute destMask values now */
const GLbitfield supportedMask = supported_buffer_bitmask(ctx, fb);
GLuint output;
for (output = 0; output < n; output++) {
mask[output] = draw_buffer_enum_to_bitmask(ctx, buffers[output]);
ASSERT(mask[output] != BAD_MASK);
mask[output] &= supportedMask;
}
destMask = mask;
}
/*
* destMask[0] may have up to four bits set
* (ex: glDrawBuffer(GL_FRONT_AND_BACK)).
* Otherwise, destMask[x] can only have one bit set.
*/
if (n > 0 && _mesa_bitcount(destMask[0]) > 1) {
GLuint count = 0, destMask0 = destMask[0];
while (destMask0) {
GLint bufIndex = ffs(destMask0) - 1;
if (fb->_ColorDrawBufferIndexes[count] != bufIndex) {
updated_drawbuffers(ctx);
fb->_ColorDrawBufferIndexes[count] = bufIndex;
}
count++;
destMask0 &= ~(1 << bufIndex);
}
fb->ColorDrawBuffer[0] = buffers[0];
fb->_NumColorDrawBuffers = count;
}
else {
GLuint count = 0;
for (buf = 0; buf < n; buf++ ) {
if (destMask[buf]) {
GLint bufIndex = ffs(destMask[buf]) - 1;
/* only one bit should be set in the destMask[buf] field */
ASSERT(_mesa_bitcount(destMask[buf]) == 1);
if (fb->_ColorDrawBufferIndexes[buf] != bufIndex) {
updated_drawbuffers(ctx);
fb->_ColorDrawBufferIndexes[buf] = bufIndex;
}
count = buf + 1;
}
else {
if (fb->_ColorDrawBufferIndexes[buf] != -1) {
updated_drawbuffers(ctx);
fb->_ColorDrawBufferIndexes[buf] = -1;
}
}
fb->ColorDrawBuffer[buf] = buffers[buf];
}
fb->_NumColorDrawBuffers = count;
}
/* set remaining outputs to -1 (GL_NONE) */
for (buf = fb->_NumColorDrawBuffers; buf < ctx->Const.MaxDrawBuffers; buf++) {
if (fb->_ColorDrawBufferIndexes[buf] != -1) {
updated_drawbuffers(ctx);
fb->_ColorDrawBufferIndexes[buf] = -1;
}
}
for (buf = n; buf < ctx->Const.MaxDrawBuffers; buf++) {
fb->ColorDrawBuffer[buf] = GL_NONE;
}
if (_mesa_is_winsys_fbo(fb)) {
/* also set context drawbuffer state */
for (buf = 0; buf < ctx->Const.MaxDrawBuffers; buf++) {
if (ctx->Color.DrawBuffer[buf] != fb->ColorDrawBuffer[buf]) {
updated_drawbuffers(ctx);
ctx->Color.DrawBuffer[buf] = fb->ColorDrawBuffer[buf];
}
}
}
}
/**
* Called by glDrawBuffersARB; specifies the destination color renderbuffers
* for N fragment program color outputs.
* \sa _mesa_DrawBuffer
* \param n number of outputs
* \param buffers array [n] of renderbuffer names. Unlike glDrawBuffer, the
* names cannot specify more than one buffer. For example,
* GL_FRONT_AND_BACK is illegal.
*/
void GLAPIENTRY
_mesa_DrawBuffers(GLsizei n, const GLenum *buffers)
{
GLint output;
GLbitfield usedBufferMask, supportedMask;
GLbitfield destMask[MAX_DRAW_BUFFERS];
GET_CURRENT_CONTEXT(ctx);
FLUSH_VERTICES(ctx, 0);
/* Turns out n==0 is a valid input that should not produce an error.
* The remaining code below correctly handles the n==0 case.
*
* From the OpenGL 3.0 specification, page 258:
* "An INVALID_VALUE error is generated if n is greater than
* MAX_DRAW_BUFFERS."
*/
if (n < 0 || n > (GLsizei) ctx->Const.MaxDrawBuffers) {
_mesa_error(ctx, GL_INVALID_VALUE, "glDrawBuffersARB(n)");
return;
}
supportedMask = supported_buffer_bitmask(ctx, ctx->DrawBuffer);
usedBufferMask = 0x0;
/* From the ES 3.0 specification, page 180:
* "If the GL is bound to the default framebuffer, then n must be 1
* and the constant must be BACK or NONE."
*/
if (_mesa_is_gles3(ctx) && _mesa_is_winsys_fbo(ctx->DrawBuffer) &&
(n != 1 || (buffers[0] != GL_NONE && buffers[0] != GL_BACK))) {
_mesa_error(ctx, GL_INVALID_OPERATION, "glDrawBuffers(buffer)");
return;
}
/* complicated error checking... */
for (output = 0; output < n; output++) {
if (buffers[output] == GL_NONE) {
destMask[output] = 0x0;
}
else {
/* Page 259 (page 275 of the PDF) in section 4.2.1 of the OpenGL 3.0
* spec (20080923) says:
*
* "If the GL is bound to a framebuffer object and DrawBuffers is
* supplied with [...] COLOR_ATTACHMENTm where m is greater than
* or equal to the value of MAX_COLOR_ATTACHMENTS, then the error
* INVALID_OPERATION results."
*/
if (_mesa_is_user_fbo(ctx->DrawBuffer) && buffers[output] >=
GL_COLOR_ATTACHMENT0 + ctx->Const.MaxDrawBuffers) {
_mesa_error(ctx, GL_INVALID_OPERATION, "glDrawBuffersARB(buffer)");
return;
}
destMask[output] = draw_buffer_enum_to_bitmask(ctx, buffers[output]);
/* From the OpenGL 3.0 specification, page 258:
* "Each buffer listed in bufs must be one of the values from tables
* 4.5 or 4.6. Otherwise, an INVALID_ENUM error is generated.
*/
if (destMask[output] == BAD_MASK) {
_mesa_error(ctx, GL_INVALID_ENUM, "glDrawBuffersARB(buffer)");
return;
}
/* From the OpenGL 4.0 specification, page 256:
* "For both the default framebuffer and framebuffer objects, the
* constants FRONT, BACK, LEFT, RIGHT, and FRONT_AND_BACK are not
* valid in the bufs array passed to DrawBuffers, and will result in
* the error INVALID_ENUM. This restriction is because these
* constants may themselves refer to multiple buffers, as shown in
* table 4.4."
* Previous versions of the OpenGL specification say INVALID_OPERATION,
* but the Khronos conformance tests expect INVALID_ENUM.
*/
if (_mesa_bitcount(destMask[output]) > 1) {
_mesa_error(ctx, GL_INVALID_ENUM, "glDrawBuffersARB(buffer)");
return;
}
/* From the OpenGL 3.0 specification, page 259:
* "If the GL is bound to the default framebuffer and DrawBuffers is
* supplied with a constant (other than NONE) that does not indicate
* any of the color buffers allocated to the GL context by the window
* system, the error INVALID_OPERATION will be generated.
*
* If the GL is bound to a framebuffer object and DrawBuffers is
* supplied with a constant from table 4.6 [...] then the error
* INVALID_OPERATION results."
*/
destMask[output] &= supportedMask;
if (destMask[output] == 0) {
_mesa_error(ctx, GL_INVALID_OPERATION,
"glDrawBuffersARB(unsupported buffer)");
return;
}
/* ES 3.0 is even more restrictive. From the ES 3.0 spec, page 180:
* "If the GL is bound to a framebuffer object, the ith buffer listed
* in bufs must be COLOR_ATTACHMENTi or NONE. [...] INVALID_OPERATION."
*/
if (_mesa_is_gles3(ctx) && _mesa_is_user_fbo(ctx->DrawBuffer) &&
buffers[output] != GL_NONE &&
buffers[output] != GL_COLOR_ATTACHMENT0 + output) {
_mesa_error(ctx, GL_INVALID_OPERATION, "glDrawBuffers(buffer)");
return;
}
/* From the OpenGL 3.0 specification, page 258:
* "Except for NONE, a buffer may not appear more than once in the
* array pointed to by bufs. Specifying a buffer more then once will
* result in the error INVALID_OPERATION."
*/
if (destMask[output] & usedBufferMask) {
_mesa_error(ctx, GL_INVALID_OPERATION,
"glDrawBuffersARB(duplicated buffer)");
return;
}
/* update bitmask */
usedBufferMask |= destMask[output];
}
}
/* OK, if we get here, there were no errors so set the new state */
_mesa_drawbuffers(ctx, n, buffers, destMask);
/*
* 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, n > 0 ? buffers[0] : GL_NONE);
}
/**
* Called by glDrawBuffersARB; specifies the destination color renderbuffers
* for N fragment program color outputs.
* \sa _mesa_DrawBuffer
* \param n number of outputs
* \param buffers array [n] of renderbuffer names. Unlike glDrawBuffer, the
* names cannot specify more than one buffer. For example,
* GL_FRONT_AND_BACK is illegal.
*/
void GLAPIENTRY
_mesa_DrawBuffers(GLsizei n, const GLenum *buffers)
{
GLint output;
GLbitfield usedBufferMask, supportedMask;
GLbitfield destMask[MAX_DRAW_BUFFERS];
GET_CURRENT_CONTEXT(ctx);
ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
/* 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;
}
supportedMask = supported_buffer_bitmask(ctx, ctx->DrawBuffer);
usedBufferMask = 0x0;
/* complicated error checking... */
for (output = 0; output < n; output++) {
if (buffers[output] == GL_NONE) {
destMask[output] = 0x0;
}
else {
destMask[output] = draw_buffer_enum_to_bitmask(buffers[output]);
if (destMask[output] == BAD_MASK
|| _mesa_bitcount(destMask[output]) > 1) {
_mesa_error(ctx, GL_INVALID_ENUM, "glDrawBuffersARB(buffer)");
return;
}
destMask[output] &= supportedMask;
if (destMask[output] == 0) {
_mesa_error(ctx, GL_INVALID_OPERATION,
"glDrawBuffersARB(unsupported buffer)");
return;
}
if (destMask[output] & usedBufferMask) {
/* can't specify a dest buffer more than once! */
_mesa_error(ctx, GL_INVALID_OPERATION,
"glDrawBuffersARB(duplicated buffer)");
return;
}
/* update bitmask */
usedBufferMask |= destMask[output];
}
}
/* OK, if we get here, there were no errors so set the new state */
_mesa_drawbuffers(ctx, n, buffers, destMask);
/*
* 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, n > 0 ? buffers[0] : GL_NONE);
}
/**
* Helper function to set the GL_DRAW_BUFFER state in the context and
* current FBO. Called via glDrawBuffer(), glDrawBuffersARB()
*
* All error checking will have been done prior to calling this function
* so nothing should go wrong at this point.
*
* \param ctx current context
* \param n number of color outputs to set
* \param buffers array[n] of colorbuffer names, like GL_LEFT.
* \param destMask array[n] of BUFFER_BIT_* bitmasks which correspond to the
* colorbuffer names. (i.e. GL_FRONT_AND_BACK =>
* BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_BACK_LEFT).
*/
void
_mesa_drawbuffers(GLcontext *ctx, GLuint n, const GLenum *buffers,
const GLbitfield *destMask)
{
struct gl_framebuffer *fb = ctx->DrawBuffer;
GLbitfield mask[MAX_DRAW_BUFFERS];
GLboolean newState = GL_FALSE;
if (!destMask) {
/* compute destMask values now */
const GLbitfield supportedMask = supported_buffer_bitmask(ctx, fb);
GLuint output;
for (output = 0; output < n; output++) {
mask[output] = draw_buffer_enum_to_bitmask(buffers[output]);
ASSERT(mask[output] != BAD_MASK);
mask[output] &= supportedMask;
}
destMask = mask;
}
/*
* If n==1, destMask[0] may have up to four bits set.
* Otherwise, destMask[x] can only have one bit set.
*/
if (n == 1) {
GLuint count = 0, destMask0 = destMask[0];
while (destMask0) {
GLint bufIndex = _mesa_ffs(destMask0) - 1;
if (fb->_ColorDrawBufferIndexes[count] != bufIndex) {
fb->_ColorDrawBufferIndexes[count] = bufIndex;
newState = GL_TRUE;
}
count++;
destMask0 &= ~(1 << bufIndex);
}
fb->ColorDrawBuffer[0] = buffers[0];
if (fb->_NumColorDrawBuffers != count) {
fb->_NumColorDrawBuffers = count;
newState = GL_TRUE;
}
}
else {
GLuint buf, count = 0;
for (buf = 0; buf < n; buf++ ) {
if (destMask[buf]) {
GLint bufIndex = _mesa_ffs(destMask[buf]) - 1;
/* only one bit should be set in the destMask[buf] field */
ASSERT(_mesa_bitcount(destMask[buf]) == 1);
if (fb->_ColorDrawBufferIndexes[buf] != bufIndex) {
fb->_ColorDrawBufferIndexes[buf] = bufIndex;
newState = GL_TRUE;
}
fb->ColorDrawBuffer[buf] = buffers[buf];
count = buf + 1;
}
else {
if (fb->_ColorDrawBufferIndexes[buf] != -1) {
fb->_ColorDrawBufferIndexes[buf] = -1;
newState = GL_TRUE;
}
}
}
/* set remaining outputs to -1 (GL_NONE) */
while (buf < ctx->Const.MaxDrawBuffers) {
if (fb->_ColorDrawBufferIndexes[buf] != -1) {
fb->_ColorDrawBufferIndexes[buf] = -1;
newState = GL_TRUE;
}
fb->ColorDrawBuffer[buf] = GL_NONE;
buf++;
}
fb->_NumColorDrawBuffers = count;
}
if (fb->Name == 0) {
/* also set context drawbuffer state */
GLuint buf;
for (buf = 0; buf < ctx->Const.MaxDrawBuffers; buf++) {
if (ctx->Color.DrawBuffer[buf] != fb->ColorDrawBuffer[buf]) {
ctx->Color.DrawBuffer[buf] = fb->ColorDrawBuffer[buf];
newState = GL_TRUE;
}
}
}
if (newState)
FLUSH_VERTICES(ctx, _NEW_BUFFERS);
}