[Mesa-dev] [PATCH 3/7] swrast: Use the fast copypixels code to implement fast glBlitFramebuffer().
Eric Anholt
eric at anholt.net
Wed Jan 4 18:04:51 PST 2012
They were meaning to do the same thing of memcpying rows, so just
write the code once.
---
src/mesa/swrast/s_blit.c | 167 +++++++++----------------------------------
src/mesa/swrast/s_copypix.c | 13 ++--
src/mesa/swrast/swrast.h | 5 ++
3 files changed, 46 insertions(+), 139 deletions(-)
diff --git a/src/mesa/swrast/s_blit.c b/src/mesa/swrast/s_blit.c
index 803ad2e..6ad4f3f 100644
--- a/src/mesa/swrast/s_blit.c
+++ b/src/mesa/swrast/s_blit.c
@@ -449,117 +449,6 @@ blit_linear(struct gl_context *ctx,
free(dstBuffer);
}
-
-/**
- * Simple case: Blit color, depth or stencil with no scaling or flipping.
- * XXX we could easily support vertical flipping here.
- */
-static void
-simple_blit(struct gl_context *ctx,
- GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
- GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
- GLbitfield buffer)
-{
- struct gl_renderbuffer *readRb, *drawRb;
- const GLint width = srcX1 - srcX0;
- const GLint height = srcY1 - srcY0;
- GLint row, srcY, dstY, yStep;
- GLint comps, bytesPerRow;
- void *rowBuffer;
-
- /* only one buffer */
- ASSERT(_mesa_bitcount(buffer) == 1);
- /* no flipping checks */
- ASSERT(srcX0 < srcX1);
- ASSERT(srcY0 < srcY1);
- ASSERT(dstX0 < dstX1);
- ASSERT(dstY0 < dstY1);
- /* size checks */
- ASSERT(srcX1 - srcX0 == dstX1 - dstX0);
- ASSERT(srcY1 - srcY0 == dstY1 - dstY0);
-
- /* From the GL_ARB_framebuffer_object spec:
- *
- * "If the source and destination buffers are identical, and the source
- * and destination rectangles overlap, the result of the blit operation
- * is undefined."
- *
- * However, we provide the expected result anyway by flipping the order of
- * the memcpy of rows.
- */
- if (srcY0 > dstY0) {
- /* src above dst: copy bottom-to-top */
- yStep = 1;
- srcY = srcY0;
- dstY = dstY0;
- }
- else {
- /* src below dst: copy top-to-bottom */
- yStep = -1;
- srcY = srcY1 - 1;
- dstY = dstY1 - 1;
- }
-
- switch (buffer) {
- case GL_COLOR_BUFFER_BIT:
- readRb = ctx->ReadBuffer->_ColorReadBuffer;
- drawRb = ctx->DrawBuffer->_ColorDrawBuffers[0];
- comps = 4;
- break;
- case GL_DEPTH_BUFFER_BIT:
- readRb = ctx->ReadBuffer->_DepthBuffer;
- drawRb = ctx->DrawBuffer->_DepthBuffer;
- comps = 1;
- break;
- case GL_STENCIL_BUFFER_BIT:
- readRb = ctx->ReadBuffer->_StencilBuffer;
- drawRb = ctx->DrawBuffer->_StencilBuffer;
- comps = 1;
- break;
- default:
- _mesa_problem(ctx, "unexpected buffer in simple_blit()");
- return;
- }
-
- ASSERT(readRb->DataType == drawRb->DataType);
-
- /* compute bytes per row */
- switch (readRb->DataType) {
- case GL_UNSIGNED_BYTE:
- bytesPerRow = comps * width * sizeof(GLubyte);
- break;
- case GL_UNSIGNED_SHORT:
- bytesPerRow = comps * width * sizeof(GLushort);
- break;
- case GL_UNSIGNED_INT:
- bytesPerRow = comps * width * sizeof(GLuint);
- break;
- case GL_FLOAT:
- bytesPerRow = comps * width * sizeof(GLfloat);
- break;
- default:
- _mesa_problem(ctx, "unexpected buffer type in simple_blit");
- return;
- }
-
- /* allocate the row buffer */
- rowBuffer = malloc(bytesPerRow);
- if (!rowBuffer) {
- _mesa_error(ctx, GL_OUT_OF_MEMORY, "glBlitFrameBufferEXT");
- return;
- }
-
- for (row = 0; row < height; row++) {
- readRb->GetRow(ctx, readRb, width, srcX0, srcY, rowBuffer);
- drawRb->PutRow(ctx, drawRb, width, dstX0, dstY, rowBuffer, NULL);
- srcY += yStep;
- dstY += yStep;
- }
-
- free(rowBuffer);
-}
-
-
/**
* Software fallback for glBlitFramebufferEXT().
*/
@@ -574,6 +463,11 @@ _swrast_BlitFramebuffer(struct gl_context *ctx,
GL_DEPTH_BUFFER_BIT,
GL_STENCIL_BUFFER_BIT
};
+ static const GLenum buffer_enums[3] = {
+ GL_COLOR,
+ GL_DEPTH,
+ GL_STENCIL,
+ };
GLint i;
if (!_mesa_clip_blit(ctx, &srcX0, &srcY0, &srcX1, &srcY1,
@@ -584,39 +478,46 @@ _swrast_BlitFramebuffer(struct gl_context *ctx,
if (SWRAST_CONTEXT(ctx)->NewState)
_swrast_validate_derived(ctx);
- swrast_render_start(ctx);
-
+ /* First, try covering whatever buffers possible using the fast 1:1 copy
+ * path.
+ */
if (srcX1 - srcX0 == dstX1 - dstX0 &&
srcY1 - srcY0 == dstY1 - dstY0 &&
srcX0 < srcX1 &&
srcY0 < srcY1 &&
dstX0 < dstX1 &&
dstY0 < dstY1) {
- /* no stretching or flipping.
- * filter doesn't matter.
- */
for (i = 0; i < 3; i++) {
if (mask & buffers[i]) {
- simple_blit(ctx, srcX0, srcY0, srcX1, srcY1,
- dstX0, dstY0, dstX1, dstY1, buffers[i]);
- }
+ if (swrast_fast_copy_pixels(ctx,
+ srcX0, srcY0,
+ srcX1 - srcX0, srcY1 - srcY0,
+ dstX0, dstY0,
+ buffer_enums[i])) {
+ mask &= ~buffers[i];
+ }
+ }
}
+
+ if (!mask)
+ return;
}
- else {
- if (filter == GL_NEAREST) {
- for (i = 0; i < 3; i++) {
- if (mask & buffers[i]) {
- blit_nearest(ctx, srcX0, srcY0, srcX1, srcY1,
- dstX0, dstY0, dstX1, dstY1, buffers[i]);
- }
- }
+
+ swrast_render_start(ctx);
+
+ if (filter == GL_NEAREST) {
+ for (i = 0; i < 3; i++) {
+ if (mask & buffers[i]) {
+ blit_nearest(ctx, srcX0, srcY0, srcX1, srcY1,
+ dstX0, dstY0, dstX1, dstY1, buffers[i]);
+ }
}
- else {
- ASSERT(filter == GL_LINEAR);
- if (mask & GL_COLOR_BUFFER_BIT) { /* depth/stencil not allowed */
- blit_linear(ctx, srcX0, srcY0, srcX1, srcY1,
- dstX0, dstY0, dstX1, dstY1);
- }
+ }
+ else {
+ ASSERT(filter == GL_LINEAR);
+ if (mask & GL_COLOR_BUFFER_BIT) { /* depth/stencil not allowed */
+ blit_linear(ctx, srcX0, srcY0, srcX1, srcY1,
+ dstX0, dstY0, dstX1, dstY1);
}
}
diff --git a/src/mesa/swrast/s_copypix.c b/src/mesa/swrast/s_copypix.c
index 8fae01f..a14b44b 100644
--- a/src/mesa/swrast/s_copypix.c
+++ b/src/mesa/swrast/s_copypix.c
@@ -422,13 +422,13 @@ copy_stencil_pixels( struct gl_context *ctx, GLint srcx, GLint srcy,
/**
- * Try to do a fast copy pixels with memcpy.
+ * Try to do a fast 1:1 blit with memcpy.
* \return GL_TRUE if successful, GL_FALSE otherwise.
*/
-static GLboolean
-fast_copy_pixels(struct gl_context *ctx,
- GLint srcX, GLint srcY, GLsizei width, GLsizei height,
- GLint dstX, GLint dstY, GLenum type)
+GLboolean
+swrast_fast_copy_pixels(struct gl_context *ctx,
+ GLint srcX, GLint srcY, GLsizei width, GLsizei height,
+ GLint dstX, GLint dstY, GLenum type)
{
struct gl_framebuffer *srcFb = ctx->ReadBuffer;
struct gl_framebuffer *dstFb = ctx->DrawBuffer;
@@ -578,7 +578,8 @@ _swrast_CopyPixels( struct gl_context *ctx,
ctx->Pixel.ZoomX != 1.0F ||
ctx->Pixel.ZoomY != 1.0F ||
ctx->_ImageTransferState) &&
- fast_copy_pixels(ctx, srcx, srcy, width, height, destx, desty, type)) {
+ swrast_fast_copy_pixels(ctx, srcx, srcy, width, height, destx, desty,
+ type)) {
/* all done */
return;
}
diff --git a/src/mesa/swrast/swrast.h b/src/mesa/swrast/swrast.h
index dd40551..468d22f 100644
--- a/src/mesa/swrast/swrast.h
+++ b/src/mesa/swrast/swrast.h
@@ -110,6 +110,11 @@ _swrast_CopyPixels( struct gl_context *ctx,
GLsizei width, GLsizei height,
GLenum type );
+extern GLboolean
+swrast_fast_copy_pixels(struct gl_context *ctx,
+ GLint srcX, GLint srcY, GLsizei width, GLsizei height,
+ GLint dstX, GLint dstY, GLenum type);
+
extern void
_swrast_DrawPixels( struct gl_context *ctx,
GLint x, GLint y,
--
1.7.7.3
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