/*
* Clear the front and/or back color buffers. Also clear the alpha
* buffer(s) if present.
*/
static void clear_color_buffers( GLcontext *ctx )
{
if (ctx->Color.SWmasking) {
clear_color_buffer_with_masking( ctx );
}
else {
GLint x = ctx->Buffer->Xmin;
GLint y = ctx->Buffer->Ymin;
GLint height = ctx->Buffer->Ymax - ctx->Buffer->Ymin + 1;
GLint width = ctx->Buffer->Xmax - ctx->Buffer->Xmin + 1;
(*ctx->Driver.Clear)( ctx, !ctx->Scissor.Enabled,
x, y, width, height );
if (ctx->RasterMask & ALPHABUF_BIT) {
/* front and/or back alpha buffers will be cleared here */
gl_clear_alpha_buffers( ctx );
}
}
if (ctx->RasterMask & FRONT_AND_BACK_BIT) {
/*** Also clear the back buffer ***/
(*ctx->Driver.SetBuffer)( ctx, GL_BACK );
if (ctx->Color.SWmasking) {
clear_color_buffer_with_masking( ctx );
}
else {
GLint x = ctx->Buffer->Xmin;
GLint y = ctx->Buffer->Ymin;
GLint height = ctx->Buffer->Ymax - ctx->Buffer->Ymin + 1;
GLint width = ctx->Buffer->Xmax - ctx->Buffer->Xmin + 1;
(*ctx->Driver.Clear)( ctx, !ctx->Scissor.Enabled,
x, y, width, height );
}
(*ctx->Driver.SetBuffer)( ctx, GL_FRONT );
}
}
/*
* Clear the front/back/left/right color buffers.
* This function is usually only called if we need to clear the
* buffers with masking.
*/
static void
clear_color_buffers(GLcontext *ctx)
{
SWcontext *swrast = SWRAST_CONTEXT(ctx);
const GLuint colorMask = *((GLuint *) &ctx->Color.ColorMask);
GLuint bufferBit;
/* loop over four possible dest color buffers */
for (bufferBit = 1; bufferBit <= 8; bufferBit = bufferBit << 1) {
if (bufferBit & ctx->Color.DrawDestMask) {
if (bufferBit == FRONT_LEFT_BIT) {
(void) (*ctx->Driver.SetDrawBuffer)( ctx, GL_FRONT_LEFT);
(void) (*swrast->Driver.SetReadBuffer)( ctx, ctx->DrawBuffer, GL_FRONT_LEFT);
}
else if (bufferBit == FRONT_RIGHT_BIT) {
(void) (*ctx->Driver.SetDrawBuffer)( ctx, GL_FRONT_RIGHT);
(void) (*swrast->Driver.SetReadBuffer)( ctx, ctx->DrawBuffer, GL_FRONT_RIGHT);
}
else if (bufferBit == BACK_LEFT_BIT) {
(void) (*ctx->Driver.SetDrawBuffer)( ctx, GL_BACK_LEFT);
(void) (*swrast->Driver.SetReadBuffer)( ctx, ctx->DrawBuffer, GL_BACK_LEFT);
}
else {
(void) (*ctx->Driver.SetDrawBuffer)( ctx, GL_BACK_RIGHT);
(void) (*swrast->Driver.SetReadBuffer)( ctx, ctx->DrawBuffer, GL_BACK_RIGHT);
}
if (colorMask != 0xffffffff) {
clear_color_buffer_with_masking(ctx);
}
else {
clear_color_buffer(ctx);
}
}
}
/* restore default read/draw buffers */
(void) (*ctx->Driver.SetDrawBuffer)( ctx, ctx->Color.DriverDrawBuffer );
(void) (*swrast->Driver.SetReadBuffer)( ctx, ctx->ReadBuffer, ctx->Pixel.DriverReadBuffer );
}
/*
* Clear the front/back/left/right color buffers.
* This function is usually only called if we need to clear the
* buffers with masking.
*/
static void
clear_color_buffers(GLcontext *ctx)
{
SWcontext *swrast = SWRAST_CONTEXT(ctx);
const GLuint colorMask = *((GLuint *) &ctx->Color.ColorMask);
GLuint bufferBit;
/* loop over four possible dest color buffers */
for (bufferBit = 1; bufferBit <= 8; bufferBit = bufferBit << 1) {
if (bufferBit & ctx->Color._DrawDestMask) {
(*swrast->Driver.SetBuffer)(ctx, ctx->DrawBuffer, bufferBit);
if (colorMask != 0xffffffff) {
clear_color_buffer_with_masking(ctx);
}
else {
clear_color_buffer(ctx);
}
}
}
/* restore default read/draw buffer */
_swrast_use_draw_buffer(ctx);
}
