/* * 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/colormac.h" #include "main/feedback.h" #include "main/formats.h" #include "main/image.h" #include "main/imports.h" #include "main/macros.h" #include "main/pack.h" #include "main/pbo.h" #include "main/state.h" #include "s_context.h" #include "s_depth.h" #include "s_span.h" #include "s_stencil.h" /** * Read pixels for format=GL_DEPTH_COMPONENT. */ static void read_depth_pixels( struct gl_context *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->Format == MESA_FORMAT_Z16); 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->Format == MESA_FORMAT_X8_Z24 || rb->Format == MESA_FORMAT_S8_Z24 || rb->Format == MESA_FORMAT_Z24_X8 || rb->Format == MESA_FORMAT_Z24_S8); ASSERT(rb->DataType == GL_UNSIGNED_INT || rb->DataType == GL_UNSIGNED_INT_24_8); 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 */ if (rb->Format == MESA_FORMAT_X8_Z24 || rb->Format == MESA_FORMAT_S8_Z24) { 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 { for (k = 0; k < width; k++) { /* Note: fill in LSByte by replication */ dest[k] = dest[k] | ((dest[k] >> 8) & 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->Format == MESA_FORMAT_Z32); 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( struct gl_context *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;jReadBuffer->_ColorReadBuffer; if (!rb) return GL_FALSE; ASSERT(rb->_BaseFormat == GL_RGBA || rb->_BaseFormat == GL_RGB || rb->_BaseFormat == GL_RG || rb->_BaseFormat == GL_RED || rb->_BaseFormat == GL_ALPHA); /* 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 converted 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(const struct gl_framebuffer *fb, GLuint n, GLfloat rgba[][4]) { const GLuint rShift = 8 - fb->Visual.redBits; const GLuint gShift = 8 - fb->Visual.greenBits; const GLuint bShift = 8 - fb->Visual.blueBits; GLfloat rScale = 1.0F / (GLfloat) ((1 << fb->Visual.redBits ) - 1); GLfloat gScale = 1.0F / (GLfloat) ((1 << fb->Visual.greenBits) - 1); GLfloat bScale = 1.0F / (GLfloat) ((1 << fb->Visual.blueBits ) - 1); GLuint i; if (fb->Visual.redBits == 0) rScale = 0; if (fb->Visual.greenBits == 0) gScale = 0; if (fb->Visual.blueBits == 0) bScale = 0; 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( struct gl_context *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); do { 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); for (row = 0; row < height; row++, y++) { /* Get float rgba pixels */ _swrast_read_rgba_span(ctx, rb, width, x, y, GL_FLOAT, rgba); /* apply fudge factor for shallow color buffers */ if ((fb->Visual.redBits < 8 && fb->Visual.redBits != 0) || (fb->Visual.greenBits < 8 && fb->Visual.greenBits != 0) || (fb->Visual.blueBits < 8 && fb->Visual.blueBits != 0)) { adjust_colors(fb, 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; } } while (0); } /** * 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(struct gl_context *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( struct gl_context *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; if (ctx->NewState) _mesa_update_state(ctx); /* 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 (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)) { pixels = _mesa_map_pbo_dest(ctx, &clippedPacking, pixels); if (pixels) { switch (format) { 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_DEPTH_STENCIL_EXT: read_depth_stencil_pixels(ctx, x, y, width, height, type, pixels, &clippedPacking); break; default: /* all other formats should be color formats */ read_rgba_pixels(ctx, x, y, width, height, format, type, pixels, &clippedPacking); } _mesa_unmap_pbo_dest(ctx, &clippedPacking); } } swrast_render_finish(ctx); }