diff options
Diffstat (limited to 'mesalib/src/mesa/swrast/s_readpix.c')
-rw-r--r-- | mesalib/src/mesa/swrast/s_readpix.c | 620 |
1 files changed, 620 insertions, 0 deletions
diff --git a/mesalib/src/mesa/swrast/s_readpix.c b/mesalib/src/mesa/swrast/s_readpix.c new file mode 100644 index 000000000..48b9408d2 --- /dev/null +++ b/mesalib/src/mesa/swrast/s_readpix.c @@ -0,0 +1,620 @@ +/* + * Mesa 3-D graphics library + * Version: 7.0.3 + * + * Copyright (C) 1999-2007 Brian Paul All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN + * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ + + +#include "main/glheader.h" +#include "main/bufferobj.h" +#include "main/colormac.h" +#include "main/convolve.h" +#include "main/context.h" +#include "main/feedback.h" +#include "main/image.h" +#include "main/macros.h" +#include "main/imports.h" +#include "main/pixel.h" +#include "main/state.h" + +#include "s_context.h" +#include "s_depth.h" +#include "s_span.h" +#include "s_stencil.h" + + +/* + * Read a block of color index pixels. + */ +static void +read_index_pixels( GLcontext *ctx, + GLint x, GLint y, + GLsizei width, GLsizei height, + GLenum type, GLvoid *pixels, + const struct gl_pixelstore_attrib *packing ) +{ + struct gl_renderbuffer *rb = ctx->ReadBuffer->_ColorReadBuffer; + GLint i; + + if (!rb) + return; + + /* width should never be > MAX_WIDTH since we did clipping earlier */ + ASSERT(width <= MAX_WIDTH); + + /* process image row by row */ + for (i = 0; i < height; i++) { + GLuint index[MAX_WIDTH]; + GLvoid *dest; + ASSERT(rb->DataType == GL_UNSIGNED_INT); + rb->GetRow(ctx, rb, width, x, y + i, index); + + dest = _mesa_image_address2d(packing, pixels, width, height, + GL_COLOR_INDEX, type, i, 0); + + _mesa_pack_index_span(ctx, width, type, dest, index, + &ctx->Pack, ctx->_ImageTransferState); + } +} + + + +/** + * Read pixels for format=GL_DEPTH_COMPONENT. + */ +static void +read_depth_pixels( GLcontext *ctx, + GLint x, GLint y, + GLsizei width, GLsizei height, + GLenum type, GLvoid *pixels, + const struct gl_pixelstore_attrib *packing ) +{ + struct gl_framebuffer *fb = ctx->ReadBuffer; + struct gl_renderbuffer *rb = fb->_DepthBuffer; + const GLboolean biasOrScale + = ctx->Pixel.DepthScale != 1.0 || ctx->Pixel.DepthBias != 0.0; + + if (!rb) + return; + + /* clipping should have been done already */ + ASSERT(x >= 0); + ASSERT(y >= 0); + ASSERT(x + width <= (GLint) rb->Width); + ASSERT(y + height <= (GLint) rb->Height); + /* width should never be > MAX_WIDTH since we did clipping earlier */ + ASSERT(width <= MAX_WIDTH); + + if (type == GL_UNSIGNED_SHORT && fb->Visual.depthBits == 16 + && !biasOrScale && !packing->SwapBytes) { + /* Special case: directly read 16-bit unsigned depth values. */ + GLint j; + ASSERT(rb->InternalFormat == GL_DEPTH_COMPONENT16); + ASSERT(rb->DataType == GL_UNSIGNED_SHORT); + for (j = 0; j < height; j++, y++) { + void *dest =_mesa_image_address2d(packing, pixels, width, height, + GL_DEPTH_COMPONENT, type, j, 0); + rb->GetRow(ctx, rb, width, x, y, dest); + } + } + else if (type == GL_UNSIGNED_INT && fb->Visual.depthBits == 24 + && !biasOrScale && !packing->SwapBytes) { + /* Special case: directly read 24-bit unsigned depth values. */ + GLint j; + ASSERT(rb->InternalFormat == GL_DEPTH_COMPONENT24); + ASSERT(rb->DataType == GL_UNSIGNED_INT); + for (j = 0; j < height; j++, y++) { + GLuint *dest = (GLuint *) + _mesa_image_address2d(packing, pixels, width, height, + GL_DEPTH_COMPONENT, type, j, 0); + GLint k; + rb->GetRow(ctx, rb, width, x, y, dest); + /* convert range from 24-bit to 32-bit */ + for (k = 0; k < width; k++) { + /* Note: put MSByte of 24-bit value into LSByte */ + dest[k] = (dest[k] << 8) | ((dest[k] >> 16) & 0xff); + } + } + } + else if (type == GL_UNSIGNED_INT && fb->Visual.depthBits == 32 + && !biasOrScale && !packing->SwapBytes) { + /* Special case: directly read 32-bit unsigned depth values. */ + GLint j; + ASSERT(rb->InternalFormat == GL_DEPTH_COMPONENT32); + ASSERT(rb->DataType == GL_UNSIGNED_INT); + for (j = 0; j < height; j++, y++) { + void *dest = _mesa_image_address2d(packing, pixels, width, height, + GL_DEPTH_COMPONENT, type, j, 0); + rb->GetRow(ctx, rb, width, x, y, dest); + } + } + else { + /* General case (slower) */ + GLint j; + for (j = 0; j < height; j++, y++) { + GLfloat depthValues[MAX_WIDTH]; + GLvoid *dest = _mesa_image_address2d(packing, pixels, width, height, + GL_DEPTH_COMPONENT, type, j, 0); + _swrast_read_depth_span_float(ctx, rb, width, x, y, depthValues); + _mesa_pack_depth_span(ctx, width, dest, type, depthValues, packing); + } + } +} + + +/** + * Read pixels for format=GL_STENCIL_INDEX. + */ +static void +read_stencil_pixels( GLcontext *ctx, + GLint x, GLint y, + GLsizei width, GLsizei height, + GLenum type, GLvoid *pixels, + const struct gl_pixelstore_attrib *packing ) +{ + struct gl_framebuffer *fb = ctx->ReadBuffer; + struct gl_renderbuffer *rb = fb->_StencilBuffer; + GLint j; + + if (!rb) + return; + + /* width should never be > MAX_WIDTH since we did clipping earlier */ + ASSERT(width <= MAX_WIDTH); + + /* process image row by row */ + for (j=0;j<height;j++,y++) { + GLvoid *dest; + GLstencil stencil[MAX_WIDTH]; + + _swrast_read_stencil_span(ctx, rb, width, x, y, stencil); + + dest = _mesa_image_address2d(packing, pixels, width, height, + GL_STENCIL_INDEX, type, j, 0); + + _mesa_pack_stencil_span(ctx, width, type, dest, stencil, packing); + } +} + + + +/** + * Optimized glReadPixels for particular pixel formats when pixel + * scaling, biasing, mapping, etc. are disabled. + * \return GL_TRUE if success, GL_FALSE if unable to do the readpixels + */ +static GLboolean +fast_read_rgba_pixels( GLcontext *ctx, + GLint x, GLint y, + GLsizei width, GLsizei height, + GLenum format, GLenum type, + GLvoid *pixels, + const struct gl_pixelstore_attrib *packing, + GLbitfield transferOps) +{ + struct gl_renderbuffer *rb = ctx->ReadBuffer->_ColorReadBuffer; + + if (!rb) + return GL_FALSE; + + ASSERT(rb->_BaseFormat == GL_RGBA || rb->_BaseFormat == GL_RGB); + + /* clipping should have already been done */ + ASSERT(x + width <= (GLint) rb->Width); + ASSERT(y + height <= (GLint) rb->Height); + + /* check for things we can't handle here */ + if (transferOps || + packing->SwapBytes || + packing->LsbFirst) { + return GL_FALSE; + } + + if (format == GL_RGBA && rb->DataType == type) { + const GLint dstStride = _mesa_image_row_stride(packing, width, + format, type); + GLubyte *dest + = (GLubyte *) _mesa_image_address2d(packing, pixels, width, height, + format, type, 0, 0); + GLint row; + ASSERT(rb->GetRow); + for (row = 0; row < height; row++) { + rb->GetRow(ctx, rb, width, x, y + row, dest); + dest += dstStride; + } + return GL_TRUE; + } + + if (format == GL_RGB && + rb->DataType == GL_UNSIGNED_BYTE && + type == GL_UNSIGNED_BYTE) { + const GLint dstStride = _mesa_image_row_stride(packing, width, + format, type); + GLubyte *dest + = (GLubyte *) _mesa_image_address2d(packing, pixels, width, height, + format, type, 0, 0); + GLint row; + ASSERT(rb->GetRow); + for (row = 0; row < height; row++) { + GLubyte tempRow[MAX_WIDTH][4]; + GLint col; + rb->GetRow(ctx, rb, width, x, y + row, tempRow); + /* convert RGBA to RGB */ + for (col = 0; col < width; col++) { + dest[col * 3 + 0] = tempRow[col][0]; + dest[col * 3 + 1] = tempRow[col][1]; + dest[col * 3 + 2] = tempRow[col][2]; + } + dest += dstStride; + } + return GL_TRUE; + } + + /* not handled */ + return GL_FALSE; +} + + +/** + * When we're using a low-precision color buffer (like 16-bit 5/6/5) + * we have to adjust our color values a bit to pass conformance. + * The problem is when a 5 or 6-bit color value is convert to an 8-bit + * value and then a floating point value, the floating point values don't + * increment uniformly as the 5 or 6-bit value is incremented. + * + * This function adjusts floating point values to compensate. + */ +static void +adjust_colors(GLcontext *ctx, GLuint n, GLfloat rgba[][4]) +{ + const GLuint rShift = 8 - ctx->Visual.redBits; + const GLuint gShift = 8 - ctx->Visual.greenBits; + const GLuint bShift = 8 - ctx->Visual.blueBits; + const GLfloat rScale = 1.0F / (GLfloat) ((1 << ctx->Visual.redBits ) - 1); + const GLfloat gScale = 1.0F / (GLfloat) ((1 << ctx->Visual.greenBits) - 1); + const GLfloat bScale = 1.0F / (GLfloat) ((1 << ctx->Visual.blueBits ) - 1); + GLuint i; + for (i = 0; i < n; i++) { + GLint r, g, b; + /* convert float back to ubyte */ + CLAMPED_FLOAT_TO_UBYTE(r, rgba[i][RCOMP]); + CLAMPED_FLOAT_TO_UBYTE(g, rgba[i][GCOMP]); + CLAMPED_FLOAT_TO_UBYTE(b, rgba[i][BCOMP]); + /* using only the N most significant bits of the ubyte value, convert to + * float in [0,1]. + */ + rgba[i][RCOMP] = (GLfloat) (r >> rShift) * rScale; + rgba[i][GCOMP] = (GLfloat) (g >> gShift) * gScale; + rgba[i][BCOMP] = (GLfloat) (b >> bShift) * bScale; + } +} + + + +/* + * Read R, G, B, A, RGB, L, or LA pixels. + */ +static void +read_rgba_pixels( GLcontext *ctx, + GLint x, GLint y, + GLsizei width, GLsizei height, + GLenum format, GLenum type, GLvoid *pixels, + const struct gl_pixelstore_attrib *packing ) +{ + SWcontext *swrast = SWRAST_CONTEXT(ctx); + GLbitfield transferOps = ctx->_ImageTransferState; + struct gl_framebuffer *fb = ctx->ReadBuffer; + struct gl_renderbuffer *rb = fb->_ColorReadBuffer; + + if (!rb) + return; + + if (type == GL_FLOAT && ((ctx->Color.ClampReadColor == GL_TRUE) || + (ctx->Color.ClampReadColor == GL_FIXED_ONLY_ARB && + rb->DataType != GL_FLOAT))) + transferOps |= IMAGE_CLAMP_BIT; + + /* Try optimized path first */ + if (fast_read_rgba_pixels(ctx, x, y, width, height, + format, type, pixels, packing, transferOps)) { + return; /* done! */ + } + + /* width should never be > MAX_WIDTH since we did clipping earlier */ + ASSERT(width <= MAX_WIDTH); + + if (ctx->Pixel.Convolution2DEnabled || ctx->Pixel.Separable2DEnabled) { + GLfloat *dest, *src, *tmpImage, *convImage; + GLint row; + + tmpImage = (GLfloat *) _mesa_malloc(width * height * 4 * sizeof(GLfloat)); + if (!tmpImage) { + _mesa_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels"); + return; + } + convImage = (GLfloat *) _mesa_malloc(width * height * 4 * sizeof(GLfloat)); + if (!convImage) { + _mesa_free(tmpImage); + _mesa_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels"); + return; + } + + /* read full RGBA, FLOAT image */ + dest = tmpImage; + for (row = 0; row < height; row++, y++) { + if (fb->Visual.rgbMode) { + _swrast_read_rgba_span(ctx, rb, width, x, y, GL_FLOAT, dest); + } + else { + GLuint index[MAX_WIDTH]; + ASSERT(rb->DataType == GL_UNSIGNED_INT); + rb->GetRow(ctx, rb, width, x, y, index); + _mesa_apply_ci_transfer_ops(ctx, + transferOps & IMAGE_SHIFT_OFFSET_BIT, + width, index); + _mesa_map_ci_to_rgba(ctx, width, index, (GLfloat (*)[4]) dest); + } + _mesa_apply_rgba_transfer_ops(ctx, + transferOps & IMAGE_PRE_CONVOLUTION_BITS, + width, (GLfloat (*)[4]) dest); + dest += width * 4; + } + + /* do convolution */ + if (ctx->Pixel.Convolution2DEnabled) { + _mesa_convolve_2d_image(ctx, &width, &height, tmpImage, convImage); + } + else { + ASSERT(ctx->Pixel.Separable2DEnabled); + _mesa_convolve_sep_image(ctx, &width, &height, tmpImage, convImage); + } + _mesa_free(tmpImage); + + /* finish transfer ops and pack the resulting image */ + src = convImage; + for (row = 0; row < height; row++) { + GLvoid *dest; + dest = _mesa_image_address2d(packing, pixels, width, height, + format, type, row, 0); + _mesa_pack_rgba_span_float(ctx, width, (GLfloat (*)[4]) src, + format, type, dest, packing, + transferOps & IMAGE_POST_CONVOLUTION_BITS); + src += width * 4; + } + _mesa_free(convImage); + } + else { + /* no convolution */ + const GLint dstStride + = _mesa_image_row_stride(packing, width, format, type); + GLfloat (*rgba)[4] = swrast->SpanArrays->attribs[FRAG_ATTRIB_COL0]; + GLint row; + GLubyte *dst + = (GLubyte *) _mesa_image_address2d(packing, pixels, width, height, + format, type, 0, 0); + + /* make sure we don't apply 1D convolution */ + transferOps &= ~(IMAGE_CONVOLUTION_BIT | + IMAGE_POST_CONVOLUTION_SCALE_BIAS); + + for (row = 0; row < height; row++, y++) { + + /* Get float rgba pixels */ + if (fb->Visual.rgbMode) { + _swrast_read_rgba_span(ctx, rb, width, x, y, GL_FLOAT, rgba); + } + else { + /* read CI and convert to RGBA */ + GLuint index[MAX_WIDTH]; + ASSERT(rb->DataType == GL_UNSIGNED_INT); + rb->GetRow(ctx, rb, width, x, y, index); + _mesa_apply_ci_transfer_ops(ctx, + transferOps & IMAGE_SHIFT_OFFSET_BIT, + width, index); + _mesa_map_ci_to_rgba(ctx, width, index, rgba); + } + + /* apply fudge factor for shallow color buffers */ + if (fb->Visual.redBits < 8 || + fb->Visual.greenBits < 8 || + fb->Visual.blueBits < 8) { + adjust_colors(ctx, width, rgba); + } + + /* pack the row of RGBA pixels into user's buffer */ + _mesa_pack_rgba_span_float(ctx, width, rgba, format, type, dst, + packing, transferOps); + + dst += dstStride; + } + } +} + + +/** + * Read combined depth/stencil values. + * We'll have already done error checking to be sure the expected + * depth and stencil buffers really exist. + */ +static void +read_depth_stencil_pixels(GLcontext *ctx, + GLint x, GLint y, + GLsizei width, GLsizei height, + GLenum type, GLvoid *pixels, + const struct gl_pixelstore_attrib *packing ) +{ + const GLboolean scaleOrBias + = ctx->Pixel.DepthScale != 1.0 || ctx->Pixel.DepthBias != 0.0; + const GLboolean stencilTransfer = ctx->Pixel.IndexShift + || ctx->Pixel.IndexOffset || ctx->Pixel.MapStencilFlag; + struct gl_renderbuffer *depthRb, *stencilRb; + + depthRb = ctx->ReadBuffer->_DepthBuffer; + stencilRb = ctx->ReadBuffer->_StencilBuffer; + + if (!depthRb || !stencilRb) + return; + + depthRb = ctx->ReadBuffer->Attachment[BUFFER_DEPTH].Renderbuffer; + stencilRb = ctx->ReadBuffer->Attachment[BUFFER_STENCIL].Renderbuffer; + + if (depthRb->_BaseFormat == GL_DEPTH_STENCIL_EXT && + stencilRb->_BaseFormat == GL_DEPTH_STENCIL_EXT && + depthRb == stencilRb && + !scaleOrBias && + !stencilTransfer) { + /* This is the ideal case. + * Reading GL_DEPTH_STENCIL pixels from combined depth/stencil buffer. + * Plus, no pixel transfer ops to worry about! + */ + GLint i; + GLint dstStride = _mesa_image_row_stride(packing, width, + GL_DEPTH_STENCIL_EXT, type); + GLubyte *dst = (GLubyte *) _mesa_image_address2d(packing, pixels, + width, height, + GL_DEPTH_STENCIL_EXT, + type, 0, 0); + for (i = 0; i < height; i++) { + depthRb->GetRow(ctx, depthRb, width, x, y + i, dst); + dst += dstStride; + } + } + else { + /* Reading GL_DEPTH_STENCIL pixels from separate depth/stencil buffers, + * or we need pixel transfer. + */ + GLint i; + depthRb = ctx->ReadBuffer->_DepthBuffer; + stencilRb = ctx->ReadBuffer->_StencilBuffer; + + for (i = 0; i < height; i++) { + GLstencil stencilVals[MAX_WIDTH]; + + GLuint *depthStencilDst = (GLuint *) + _mesa_image_address2d(packing, pixels, width, height, + GL_DEPTH_STENCIL_EXT, type, i, 0); + + _swrast_read_stencil_span(ctx, stencilRb, width, + x, y + i, stencilVals); + + if (!scaleOrBias && !stencilTransfer + && ctx->ReadBuffer->Visual.depthBits == 24) { + /* ideal case */ + GLuint zVals[MAX_WIDTH]; /* 24-bit values! */ + GLint j; + ASSERT(depthRb->DataType == GL_UNSIGNED_INT); + /* note, we've already been clipped */ + depthRb->GetRow(ctx, depthRb, width, x, y + i, zVals); + for (j = 0; j < width; j++) { + depthStencilDst[j] = (zVals[j] << 8) | (stencilVals[j] & 0xff); + } + } + else { + /* general case */ + GLfloat depthVals[MAX_WIDTH]; + _swrast_read_depth_span_float(ctx, depthRb, width, x, y + i, + depthVals); + _mesa_pack_depth_stencil_span(ctx, width, depthStencilDst, + depthVals, stencilVals, packing); + } + } + } +} + + + +/** + * Software fallback routine for ctx->Driver.ReadPixels(). + * By time we get here, all error checking will have been done. + */ +void +_swrast_ReadPixels( GLcontext *ctx, + GLint x, GLint y, GLsizei width, GLsizei height, + GLenum format, GLenum type, + const struct gl_pixelstore_attrib *packing, + GLvoid *pixels ) +{ + SWcontext *swrast = SWRAST_CONTEXT(ctx); + struct gl_pixelstore_attrib clippedPacking = *packing; + + /* Need to do swrast_render_start() before clipping or anything else + * since this is where a driver may grab the hw lock and get an updated + * window size. + */ + swrast_render_start(ctx); + + if (ctx->NewState) + _mesa_update_state(ctx); + + if (swrast->NewState) + _swrast_validate_derived( ctx ); + + /* Do all needed clipping here, so that we can forget about it later */ + if (!_mesa_clip_readpixels(ctx, &x, &y, &width, &height, &clippedPacking)) { + /* The ReadPixels region is totally outside the window bounds */ + swrast_render_finish(ctx); + return; + } + + pixels = _mesa_map_pbo_dest(ctx, &clippedPacking, pixels); + if (!pixels) + return; + + switch (format) { + case GL_COLOR_INDEX: + read_index_pixels(ctx, x, y, width, height, type, pixels, + &clippedPacking); + break; + case GL_STENCIL_INDEX: + read_stencil_pixels(ctx, x, y, width, height, type, pixels, + &clippedPacking); + break; + case GL_DEPTH_COMPONENT: + read_depth_pixels(ctx, x, y, width, height, type, pixels, + &clippedPacking); + break; + case GL_RED: + case GL_GREEN: + case GL_BLUE: + case GL_ALPHA: + case GL_RGB: + case GL_LUMINANCE: + case GL_LUMINANCE_ALPHA: + case GL_RGBA: + case GL_BGR: + case GL_BGRA: + case GL_ABGR_EXT: + read_rgba_pixels(ctx, x, y, width, height, + format, type, pixels, &clippedPacking); + break; + case GL_DEPTH_STENCIL_EXT: + read_depth_stencil_pixels(ctx, x, y, width, height, + type, pixels, &clippedPacking); + break; + default: + _mesa_problem(ctx, "unexpected format in _swrast_ReadPixels"); + /* don't return yet, clean-up */ + } + + swrast_render_finish(ctx); + + _mesa_unmap_pbo_dest(ctx, &clippedPacking); +} |