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authorBrian Paul <brian.paul@tungstengraphics.com>2006-03-02 03:37:18 +0000
committerBrian Paul <brian.paul@tungstengraphics.com>2006-03-02 03:37:18 +0000
commitc241d3b06a5c996cb8415a6ada23288621c1d254 (patch)
treebcdae36e663b3c5e9ad29029f4f729efd620d5e2 /src/mesa/swrast/s_blit.c
parent93da673904d4c520d3fbd2210e53777bf1598ac6 (diff)
implementation of _swrast_BlitFramebuffer()
Diffstat (limited to 'src/mesa/swrast/s_blit.c')
-rw-r--r--src/mesa/swrast/s_blit.c758
1 files changed, 754 insertions, 4 deletions
diff --git a/src/mesa/swrast/s_blit.c b/src/mesa/swrast/s_blit.c
index 0d08a4effc..5aec4aad03 100644
--- a/src/mesa/swrast/s_blit.c
+++ b/src/mesa/swrast/s_blit.c
@@ -28,13 +28,763 @@
#include "s_context.h"
+#define ABS(X) ((X) < 0 ? -(X) : (X))
+
+
+/**
+ * Generate a row resampler function for GL_NEAREST mode.
+ */
+#define RESAMPLE(NAME, PIXELTYPE, SIZE) \
+static void \
+NAME(GLint srcWidth, GLint dstWidth, \
+ const GLvoid *srcBuffer, GLvoid *dstBuffer, \
+ GLboolean flip) \
+{ \
+ const PIXELTYPE *src = (const PIXELTYPE *) srcBuffer;\
+ PIXELTYPE *dst = (PIXELTYPE *) dstBuffer; \
+ GLint dstCol; \
+ \
+ if (flip) { \
+ for (dstCol = 0; dstCol < dstWidth; dstCol++) { \
+ GLint srcCol = (dstCol * srcWidth) / dstWidth; \
+ ASSERT(srcCol >= 0); \
+ ASSERT(srcCol < srcWidth); \
+ srcCol = srcWidth - 1 - srcCol; /* flip */ \
+ if (SIZE == 1) { \
+ dst[dstCol] = src[srcCol]; \
+ } \
+ else if (SIZE == 2) { \
+ dst[dstCol*2+0] = src[srcCol*2+0]; \
+ dst[dstCol*2+1] = src[srcCol*2+1]; \
+ } \
+ else if (SIZE == 4) { \
+ dst[dstCol*4+0] = src[srcCol*4+0]; \
+ dst[dstCol*4+1] = src[srcCol*4+1]; \
+ dst[dstCol*4+2] = src[srcCol*4+2]; \
+ dst[dstCol*4+3] = src[srcCol*4+3]; \
+ } \
+ } \
+ } \
+ else { \
+ for (dstCol = 0; dstCol < dstWidth; dstCol++) { \
+ GLint srcCol = (dstCol * srcWidth) / dstWidth; \
+ ASSERT(srcCol >= 0); \
+ ASSERT(srcCol < srcWidth); \
+ if (SIZE == 1) { \
+ dst[dstCol] = src[srcCol]; \
+ } \
+ else if (SIZE == 2) { \
+ dst[dstCol*2+0] = src[srcCol*2+0]; \
+ dst[dstCol*2+1] = src[srcCol*2+1]; \
+ } \
+ else if (SIZE == 4) { \
+ dst[dstCol*4+0] = src[srcCol*4+0]; \
+ dst[dstCol*4+1] = src[srcCol*4+1]; \
+ dst[dstCol*4+2] = src[srcCol*4+2]; \
+ dst[dstCol*4+3] = src[srcCol*4+3]; \
+ } \
+ } \
+ } \
+}
+
+/**
+ * Resamplers for 1, 2, 4, 8 and 16-byte pixels.
+ */
+RESAMPLE(resample_row_1, GLubyte, 1)
+RESAMPLE(resample_row_2, GLushort, 1)
+RESAMPLE(resample_row_4, GLuint, 1)
+RESAMPLE(resample_row_8, GLuint, 2)
+RESAMPLE(resample_row_16, GLuint, 4)
+
+
+/**
+ * Blit color, depth or stencil with GL_NEAREST filtering.
+ */
+static void
+blit_nearest(GLcontext *ctx,
+ GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
+ GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
+ GLenum buffer)
+{
+ struct gl_renderbuffer *readRb, *drawRb;
+
+ const GLint srcWidth = ABS(srcX1 - srcX0);
+ const GLint dstWidth = ABS(dstX1 - dstX0);
+ const GLint srcHeight = ABS(srcY1 - srcY0);
+ const GLint dstHeight = ABS(dstY1 - dstY0);
+
+ const GLint srcXpos = MIN2(srcX0, srcX1);
+ const GLint srcYpos = MIN2(srcY0, srcY1);
+ const GLint dstXpos = MIN2(dstX0, dstX1);
+ const GLint dstYpos = MIN2(dstY0, dstY1);
+
+ const GLboolean invertX = (srcX1 < srcX0) ^ (dstX1 < dstX0);
+ const GLboolean invertY = (srcY1 < srcY0) ^ (dstY1 < dstY0);
+
+ GLint dstRow;
+
+ GLint comps, pixelSize;
+ GLvoid *srcBuffer, *dstBuffer;
+ GLint prevY = -1;
+
+ typedef void (*resample_func)(GLint srcWidth, GLint dstWidth,
+ const GLvoid *srcBuffer, GLvoid *dstBuffer,
+ GLboolean flip);
+ resample_func resampleRow;
+
+ switch (buffer) {
+ case GL_COLOR_BUFFER_BIT:
+ readRb = ctx->ReadBuffer->_ColorReadBuffer;
+ drawRb = ctx->DrawBuffer->_ColorDrawBuffers[0][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 blit_nearest()");
+ return;
+ }
+
+ switch (readRb->DataType) {
+ case GL_UNSIGNED_BYTE:
+ pixelSize = comps * sizeof(GLubyte);
+ break;
+ case GL_UNSIGNED_SHORT:
+ pixelSize = comps * sizeof(GLushort);
+ break;
+ case GL_UNSIGNED_INT:
+ pixelSize = comps * sizeof(GLuint);
+ break;
+ case GL_FLOAT:
+ pixelSize = comps * sizeof(GLfloat);
+ break;
+ default:
+ _mesa_problem(ctx, "unexpected buffer type (0x%x) in blit_nearest",
+ readRb->DataType);
+ return;
+ }
+
+ /* choose row resampler */
+ switch (pixelSize) {
+ case 1:
+ resampleRow = resample_row_1;
+ break;
+ case 2:
+ resampleRow = resample_row_2;
+ break;
+ case 4:
+ resampleRow = resample_row_4;
+ break;
+ case 8:
+ resampleRow = resample_row_8;
+ break;
+ case 16:
+ resampleRow = resample_row_16;
+ break;
+ default:
+ _mesa_problem(ctx, "unexpected pixel size (%d) in blit_nearest",
+ pixelSize);
+ return;
+ }
+
+ /* allocate the src/dst row buffers */
+ srcBuffer = _mesa_malloc(pixelSize * srcWidth);
+ if (!srcBuffer) {
+ _mesa_error(ctx, GL_OUT_OF_MEMORY, "glBlitFrameBufferEXT");
+ return;
+ }
+ dstBuffer = _mesa_malloc(pixelSize * dstWidth);
+ if (!dstBuffer) {
+ _mesa_free(srcBuffer);
+ _mesa_error(ctx, GL_OUT_OF_MEMORY, "glBlitFrameBufferEXT");
+ return;
+ }
+
+ for (dstRow = 0; dstRow < dstHeight; dstRow++) {
+ const GLint dstY = dstYpos + dstRow;
+ GLint srcRow = (dstRow * srcHeight) / dstHeight;
+ GLint srcY;
+
+ ASSERT(srcRow >= 0);
+ ASSERT(srcRow < srcHeight);
+
+ if (invertY) {
+ srcRow = srcHeight - 1 - srcRow;
+ }
+
+ srcY = srcYpos + srcRow;
+
+ /* get pixel row from source and resample to match dest width */
+ if (prevY != srcY) {
+ readRb->GetRow(ctx, readRb, srcWidth, srcXpos, srcY, srcBuffer);
+ (*resampleRow)(srcWidth, dstWidth, srcBuffer, dstBuffer, invertX);
+ prevY = srcY;
+ }
+
+ /* store pixel row in destination */
+ drawRb->PutRow(ctx, drawRb, dstWidth, dstXpos, dstY, dstBuffer, NULL);
+ }
+
+ _mesa_free(srcBuffer);
+ _mesa_free(dstBuffer);
+}
+
+
+
+#define LERP(T, A, B) ( (A) + (T) * ((B) - (A)) )
+
+static INLINE GLfloat
+lerp_2d(GLfloat a, GLfloat b,
+ GLfloat v00, GLfloat v10, GLfloat v01, GLfloat v11)
+{
+ const GLfloat temp0 = LERP(a, v00, v10);
+ const GLfloat temp1 = LERP(a, v01, v11);
+ return LERP(b, temp0, temp1);
+}
+
+
+/**
+ * Bilinear interpolation of two source rows.
+ * GLubyte pixels.
+ */
+static void
+resample_linear_row_ub(GLint srcWidth, GLint dstWidth,
+ const GLvoid *srcBuffer0, const GLvoid *srcBuffer1,
+ GLvoid *dstBuffer, GLboolean flip, GLfloat rowWeight)
+{
+ const GLubyte (*srcColor0)[4] = (const GLubyte (*)[4]) srcBuffer0;
+ const GLubyte (*srcColor1)[4] = (const GLubyte (*)[4]) srcBuffer1;
+ GLubyte (*dstColor)[4] = (GLubyte (*)[4]) dstBuffer;
+ const GLfloat dstWidthF = (GLfloat) dstWidth;
+ GLint dstCol;
+
+ for (dstCol = 0; dstCol < dstWidth; dstCol++) {
+ const GLfloat srcCol = (dstCol * srcWidth) / dstWidthF;
+ GLint srcCol0 = IFLOOR(srcCol);
+ GLint srcCol1 = srcCol0 + 1;
+ GLfloat colWeight = srcCol - srcCol0; /* fractional part of srcCol */
+ GLfloat red, green, blue, alpha;
+
+ ASSERT(srcCol0 >= 0);
+ ASSERT(srcCol0 < srcWidth);
+ ASSERT(srcCol1 <= srcWidth);
+
+ if (srcCol1 == srcWidth) {
+ /* last column fudge */
+ srcCol1--;
+ colWeight = 0.0;
+ }
+
+ if (flip) {
+ srcCol0 = srcWidth - 1 - srcCol0;
+ srcCol1 = srcWidth - 1 - srcCol1;
+ }
+
+ red = lerp_2d(colWeight, rowWeight,
+ srcColor0[srcCol0][RCOMP], srcColor0[srcCol1][RCOMP],
+ srcColor1[srcCol0][RCOMP], srcColor1[srcCol1][RCOMP]);
+ green = lerp_2d(colWeight, rowWeight,
+ srcColor0[srcCol0][GCOMP], srcColor0[srcCol1][GCOMP],
+ srcColor1[srcCol0][GCOMP], srcColor1[srcCol1][GCOMP]);
+ blue = lerp_2d(colWeight, rowWeight,
+ srcColor0[srcCol0][BCOMP], srcColor0[srcCol1][BCOMP],
+ srcColor1[srcCol0][BCOMP], srcColor1[srcCol1][BCOMP]);
+ alpha = lerp_2d(colWeight, rowWeight,
+ srcColor0[srcCol0][ACOMP], srcColor0[srcCol1][ACOMP],
+ srcColor1[srcCol0][ACOMP], srcColor1[srcCol1][ACOMP]);
+
+ dstColor[dstCol][RCOMP] = IFLOOR(red);
+ dstColor[dstCol][GCOMP] = IFLOOR(green);
+ dstColor[dstCol][BCOMP] = IFLOOR(blue);
+ dstColor[dstCol][ACOMP] = IFLOOR(alpha);
+ }
+}
+
+
+
+/**
+ * Bilinear filtered blit (color only).
+ */
+static void
+blit_linear(GLcontext *ctx,
+ GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
+ GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1)
+{
+ struct gl_renderbuffer *readRb = ctx->ReadBuffer->_ColorReadBuffer;
+ struct gl_renderbuffer *drawRb = ctx->DrawBuffer->_ColorDrawBuffers[0][0];
+
+ const GLint srcWidth = ABS(srcX1 - srcX0);
+ const GLint dstWidth = ABS(dstX1 - dstX0);
+ const GLint srcHeight = ABS(srcY1 - srcY0);
+ const GLint dstHeight = ABS(dstY1 - dstY0);
+ const GLfloat dstHeightF = (GLfloat) dstHeight;
+
+ const GLint srcXpos = MIN2(srcX0, srcX1);
+ const GLint srcYpos = MIN2(srcY0, srcY1);
+ const GLint dstXpos = MIN2(dstX0, dstX1);
+ const GLint dstYpos = MIN2(dstY0, dstY1);
+
+ const GLboolean invertX = (srcX1 < srcX0) ^ (dstX1 < dstX0);
+ const GLboolean invertY = (srcY1 < srcY0) ^ (dstY1 < dstY0);
+
+ GLint dstRow;
+
+ GLint pixelSize;
+ GLvoid *srcBuffer0, *srcBuffer1;
+ GLint srcBufferY0 = -1, srcBufferY1 = -1;
+ GLvoid *dstBuffer;
+
+ switch (readRb->DataType) {
+ case GL_UNSIGNED_BYTE:
+ pixelSize = 4 * sizeof(GLubyte);
+ break;
+ case GL_UNSIGNED_SHORT:
+ pixelSize = 4 * sizeof(GLushort);
+ break;
+ case GL_UNSIGNED_INT:
+ pixelSize = 4 * sizeof(GLuint);
+ break;
+ case GL_FLOAT:
+ pixelSize = 4 * sizeof(GLfloat);
+ break;
+ default:
+ _mesa_problem(ctx, "unexpected buffer type (0x%x) in blit_nearest",
+ readRb->DataType);
+ return;
+ }
+
+ /* Allocate the src/dst row buffers.
+ * Keep two adjacent src rows around for bilinear sampling.
+ */
+ srcBuffer0 = _mesa_malloc(pixelSize * srcWidth);
+ if (!srcBuffer0) {
+ _mesa_error(ctx, GL_OUT_OF_MEMORY, "glBlitFrameBufferEXT");
+ return;
+ }
+ srcBuffer1 = _mesa_malloc(pixelSize * srcWidth);
+ if (!srcBuffer1) {
+ _mesa_free(srcBuffer0);
+ _mesa_error(ctx, GL_OUT_OF_MEMORY, "glBlitFrameBufferEXT");
+ return;
+ }
+ dstBuffer = _mesa_malloc(pixelSize * dstWidth);
+ if (!dstBuffer) {
+ _mesa_free(srcBuffer0);
+ _mesa_free(srcBuffer1);
+ _mesa_error(ctx, GL_OUT_OF_MEMORY, "glBlitFrameBufferEXT");
+ return;
+ }
+
+ for (dstRow = 0; dstRow < dstHeight; dstRow++) {
+ const GLint dstY = dstYpos + dstRow;
+ const GLfloat srcRow = (dstRow * srcHeight) / dstHeightF;
+ GLint srcRow0 = IFLOOR(srcRow);
+ GLint srcRow1 = srcRow0 + 1;
+ GLfloat rowWeight = srcRow - srcRow0; /* fractional part of srcRow */
+
+ ASSERT(srcRow >= 0);
+ ASSERT(srcRow < srcHeight);
+
+ if (srcRow1 == srcHeight) {
+ /* last row fudge */
+ srcRow1 = srcRow0;
+ rowWeight = 0.0;
+ }
+
+ if (invertY) {
+ srcRow0 = srcHeight - 1 - srcRow0;
+ srcRow1 = srcHeight - 1 - srcRow1;
+ }
+
+ srcY0 = srcYpos + srcRow0;
+ srcY1 = srcYpos + srcRow1;
+
+ /* get the two source rows */
+ if (srcY0 == srcBufferY0 && srcY1 == srcBufferY1) {
+ /* use same source row buffers again */
+ }
+ else if (srcY0 == srcBufferY1) {
+ /* move buffer1 into buffer0 by swapping pointers */
+ GLvoid *tmp = srcBuffer0;
+ srcBuffer0 = srcBuffer1;
+ srcBuffer1 = tmp;
+ /* get y1 row */
+ readRb->GetRow(ctx, readRb, srcWidth, srcXpos, srcY1, srcBuffer1);
+ srcBufferY0 = srcY0;
+ srcBufferY1 = srcY1;
+ }
+ else {
+ /* get both new rows */
+ readRb->GetRow(ctx, readRb, srcWidth, srcXpos, srcY0, srcBuffer0);
+ readRb->GetRow(ctx, readRb, srcWidth, srcXpos, srcY1, srcBuffer1);
+ srcBufferY0 = srcY0;
+ srcBufferY1 = srcY1;
+ }
+
+ if (readRb->DataType == GL_UNSIGNED_BYTE) {
+ resample_linear_row_ub(srcWidth, dstWidth, srcBuffer0, srcBuffer1,
+ dstBuffer, invertX, rowWeight);
+ }
+ else {
+ _mesa_problem(ctx, "Unsupported color channel type in sw blit");
+ break;
+ }
+
+ /* store pixel row in destination */
+ drawRb->PutRow(ctx, drawRb, dstWidth, dstXpos, dstY, dstBuffer, NULL);
+ }
+
+ _mesa_free(srcBuffer0);
+ _mesa_free(srcBuffer1);
+ _mesa_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(GLcontext *ctx,
+ GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
+ GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
+ GLenum 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);
+
+ /* determine if copy should be bottom-to-top or top-to-bottom */
+ 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][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 = _mesa_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;
+ }
+
+ _mesa_free(rowBuffer);
+}
+
+
+/**
+ * Clip dst coords against Xmax (or Ymax).
+ */
+static INLINE void
+clip_right_or_top(GLint *srcX0, GLint *srcX1,
+ GLint *dstX0, GLint *dstX1,
+ GLint maxValue)
+{
+ GLfloat t, bias;
+
+ if (*dstX1 > maxValue) {
+ /* X1 outside right edge */
+ ASSERT(*dstX0 < maxValue); /* X0 should be inside right edge */
+ t = (GLfloat) (maxValue - *dstX0) / (GLfloat) (*dstX1 - *dstX0);
+ /* chop off [t, 1] part */
+ ASSERT(t >= 0.0 && t <= 1.0);
+ *dstX1 = maxValue;
+ bias = (*srcX0 < *srcX1) ? 0.5 : -0.5;
+ *srcX1 = *srcX0 + (GLint) (t * (*srcX1 - *srcX0) + bias);
+ }
+ else if (*dstX0 > maxValue) {
+ /* X0 outside right edge */
+ ASSERT(*dstX1 < maxValue); /* X1 should be inside right edge */
+ t = (GLfloat) (maxValue - *dstX1) / (GLfloat) (*dstX0 - *dstX1);
+ /* chop off [t, 1] part */
+ ASSERT(t >= 0.0 && t <= 1.0);
+ *dstX0 = maxValue;
+ bias = (*srcX0 < *srcX1) ? -0.5 : 0.5;
+ *srcX0 = *srcX1 + (GLint) (t * (*srcX0 - *srcX1) + bias);
+ }
+}
+
+
+/**
+ * Clip dst coords against Xmin (or Ymin).
+ */
+static INLINE void
+clip_left_or_bottom(GLint *srcX0, GLint *srcX1,
+ GLint *dstX0, GLint *dstX1,
+ GLint minValue)
+{
+ GLfloat t, bias;
+
+ if (*dstX0 < minValue) {
+ /* X0 outside left edge */
+ ASSERT(*dstX1 > minValue); /* X1 should be inside left edge */
+ t = (GLfloat) (minValue - *dstX0) / (GLfloat) (*dstX1 - *dstX0);
+ /* chop off [0, t] part */
+ ASSERT(t >= 0.0 && t <= 1.0);
+ *dstX0 = minValue;
+ bias = (*srcX0 < *srcX1) ? 0.5 : -0.5; /* flipped??? */
+ *srcX0 = *srcX0 + (GLint) (t * (*srcX1 - *srcX0) + bias);
+ }
+ else if (*dstX1 < minValue) {
+ /* X1 outside left edge */
+ ASSERT(*dstX0 > minValue); /* X0 should be inside left edge */
+ t = (GLfloat) (minValue - *dstX1) / (GLfloat) (*dstX0 - *dstX1);
+ /* chop off [0, t] part */
+ ASSERT(t >= 0.0 && t <= 1.0);
+ *dstX1 = minValue;
+ bias = (*srcX0 < *srcX1) ? 0.5 : -0.5;
+ *srcX1 = *srcX1 + (GLint) (t * (*srcX0 - *srcX1) + bias);
+ }
+}
+
+
+/**
+ * Do clipping of blit src/dest rectangles.
+ * The dest rect is clipped against both the buffer bounds and scissor bounds.
+ * The src rect is just clipped against the buffer bounds.
+ *
+ * When either the src or dest rect is clipped, the other is also clipped
+ * proportionately!
+ *
+ * Note that X0 need not be less than X1 (same for Y) for either the source
+ * and dest rects. That makes the clipping a little trickier.
+ *
+ * \return GL_TRUE if anything is left to draw, GL_FALSE if totally clipped
+ */
+static GLboolean
+clip_blit(GLcontext *ctx,
+ GLint *srcX0, GLint *srcY0, GLint *srcX1, GLint *srcY1,
+ GLint *dstX0, GLint *dstY0, GLint *dstX1, GLint *dstY1)
+{
+ const GLint srcXmin = 0;
+ const GLint srcXmax = ctx->ReadBuffer->Width;
+ const GLint srcYmin = 0;
+ const GLint srcYmax = ctx->ReadBuffer->Height;
+
+ /* these include scissor bounds */
+ const GLint dstXmin = ctx->DrawBuffer->_Xmin;
+ const GLint dstXmax = ctx->DrawBuffer->_Xmax;
+ const GLint dstYmin = ctx->DrawBuffer->_Ymin;
+ const GLint dstYmax = ctx->DrawBuffer->_Ymax;
+
+ /*
+ printf("PreClipX: src: %d .. %d dst: %d .. %d\n",
+ *srcX0, *srcX1, *dstX0, *dstX1);
+ printf("PreClipY: src: %d .. %d dst: %d .. %d\n",
+ *srcY0, *srcY1, *dstY0, *dstY1);
+ */
+
+ /* trivial rejection tests */
+ if (*dstX0 == *dstX1)
+ return GL_FALSE; /* no width */
+ if (*dstX0 <= dstXmin && *dstX1 <= dstXmin)
+ return GL_FALSE; /* totally out (left) of bounds */
+ if (*dstX0 >= dstXmax && *dstX1 >= dstXmax)
+ return GL_FALSE; /* totally out (right) of bounds */
+
+ if (*dstY0 == *dstY1)
+ return GL_FALSE;
+ if (*dstY0 <= dstYmin && *dstY1 <= dstYmin)
+ return GL_FALSE;
+ if (*dstY0 >= dstYmax && *dstY1 >= dstYmax)
+ return GL_FALSE;
+
+ if (*srcX0 == *srcX1)
+ return GL_FALSE;
+ if (*srcX0 <= srcXmin && *srcX1 <= srcXmin)
+ return GL_FALSE;
+ if (*srcX0 >= srcXmax && *srcX1 >= srcXmax)
+ return GL_FALSE;
+
+ if (*srcY0 == *srcY1)
+ return GL_FALSE;
+ if (*srcY0 <= srcYmin && *srcY1 <= srcYmin)
+ return GL_FALSE;
+ if (*srcY0 >= srcYmax && *srcY1 >= srcYmax)
+ return GL_FALSE;
+
+ /*
+ * dest clip
+ */
+ clip_right_or_top(srcX0, srcX1, dstX0, dstX1, dstXmax);
+ clip_right_or_top(srcY0, srcY1, dstY0, dstY1, dstYmax);
+ clip_left_or_bottom(srcX0, srcX1, dstX0, dstX1, dstXmin);
+ clip_left_or_bottom(srcY0, srcY1, dstY0, dstY1, dstYmin);
+
+ /*
+ * src clip (just swap src/dst values from above)
+ */
+ clip_right_or_top(dstX0, dstX1, srcX0, srcX1, srcXmax);
+ clip_right_or_top(dstY0, dstY1, srcY0, srcY1, srcYmax);
+ clip_left_or_bottom(dstX0, dstX1, srcX0, srcX1, srcXmin);
+ clip_left_or_bottom(dstY0, dstY1, srcY0, srcY1, srcYmin);
+
+ /*
+ printf("PostClipX: src: %d .. %d dst: %d .. %d\n",
+ *srcX0, *srcX1, *dstX0, *dstX1);
+ printf("PostClipY: src: %d .. %d dst: %d .. %d\n",
+ *srcY0, *srcY1, *dstY0, *dstY1);
+ */
+
+ ASSERT(*dstX0 >= dstXmin);
+ ASSERT(*dstX0 <= dstXmax);
+ ASSERT(*dstX1 >= dstXmin);
+ ASSERT(*dstX1 <= dstXmax);
+
+ ASSERT(*dstY0 >= dstYmin);
+ ASSERT(*dstY0 <= dstYmax);
+ ASSERT(*dstY1 >= dstYmin);
+ ASSERT(*dstY1 <= dstYmax);
+
+ ASSERT(*srcX0 >= srcXmin);
+ ASSERT(*srcX0 <= srcXmax);
+ ASSERT(*srcX1 >= srcXmin);
+ ASSERT(*srcX1 <= srcXmax);
+
+ ASSERT(*srcY0 >= srcYmin);
+ ASSERT(*srcY0 <= srcYmax);
+ ASSERT(*srcY1 >= srcYmin);
+ ASSERT(*srcY1 <= srcYmax);
+
+ return GL_TRUE;
+}
+
+
/**
* Software fallback for glBlitFramebufferEXT().
*/
void
-_swrast_blit_framebuffer(GLcontext *ctx,
- GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
- GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
- GLbitfield mask, GLenum filter)
+_swrast_BlitFramebuffer(GLcontext *ctx,
+ GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
+ GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
+ GLbitfield mask, GLenum filter)
{
+ SWcontext *swrast = SWRAST_CONTEXT(ctx);
+ static const GLint buffers[3] = {
+ GL_COLOR_BUFFER_BIT,
+ GL_DEPTH_BUFFER_BIT,
+ GL_STENCIL_BUFFER_BIT
+ };
+ GLint i;
+
+ if (!clip_blit(ctx, &srcX0, &srcY0, &srcX1, &srcY1,
+ &dstX0, &dstY0, &dstX1, &dstY1)) {
+ return;
+ }
+
+ RENDER_START(swrast, ctx);
+
+ 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]);
+ }
+ }
+ }
+ 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]);
+ }
+ }
+ }
+ 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);
+ }
+ }
+ }
+
+ RENDER_FINISH(swrast, ctx);
}