From 5038d839b8e4d5926ee2aeaa4a66367ba99a31c6 Mon Sep 17 00:00:00 2001 From: Iago Toral Quiroga Date: Thu, 23 Oct 2014 10:04:56 +0200 Subject: [PATCH] mesa: use _mesa_format_convert to implement glReadPixels. Reviewed-by: Jason Ekstrand --- src/mesa/main/readpix.c | 326 +++++++++++++++++++++++----------------- 1 file changed, 184 insertions(+), 142 deletions(-) diff --git a/src/mesa/main/readpix.c b/src/mesa/main/readpix.c index b09cf54994a..c589ca4e202 100644 --- a/src/mesa/main/readpix.c +++ b/src/mesa/main/readpix.c @@ -39,6 +39,8 @@ #include "state.h" #include "glformats.h" #include "fbobject.h" +#include "format_utils.h" +#include "pixeltransfer.h" /** @@ -405,174 +407,214 @@ read_stencil_pixels( struct gl_context *ctx, ctx->Driver.UnmapRenderbuffer(ctx, rb); } - -/** - * Try to do glReadPixels of RGBA data using swizzle. - * \return GL_TRUE if successful, GL_FALSE otherwise (use the slow path) +/* + * Read R, G, B, A, RGB, L, or LA pixels. */ -static GLboolean -read_rgba_pixels_swizzle(struct gl_context *ctx, - GLint x, GLint y, - GLsizei width, GLsizei height, - GLenum format, GLenum type, - GLvoid *pixels, - const struct gl_pixelstore_attrib *packing) +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 ) { - struct gl_renderbuffer *rb = ctx->ReadBuffer->_ColorReadBuffer; + GLbitfield transferOps; + bool dst_is_integer, dst_is_luminance, needs_rebase; + int dst_stride, src_stride, rb_stride; + uint32_t dst_format, src_format; GLubyte *dst, *map; - int dstStride, stride, j; - GLboolean swizzle_rb = GL_FALSE, copy_xrgb = GL_FALSE; - - /* XXX we could check for other swizzle/special cases here as needed */ - if (rb->Format == MESA_FORMAT_R8G8B8A8_UNORM && - format == GL_BGRA && - type == GL_UNSIGNED_INT_8_8_8_8_REV && - !ctx->Pack.SwapBytes) { - swizzle_rb = GL_TRUE; - } - else if (rb->Format == MESA_FORMAT_B8G8R8X8_UNORM && - format == GL_BGRA && - type == GL_UNSIGNED_INT_8_8_8_8_REV && - !ctx->Pack.SwapBytes) { - copy_xrgb = GL_TRUE; - } - else { - return GL_FALSE; - } + mesa_format rb_format; + bool needs_rgba; + void *rgba, *src; + bool src_is_uint = false; + uint8_t rebase_swizzle[4]; + struct gl_framebuffer *fb = ctx->ReadBuffer; + struct gl_renderbuffer *rb = fb->_ColorReadBuffer; - dstStride = _mesa_image_row_stride(packing, width, format, type); + if (!rb) + return; + + transferOps = get_readpixels_transfer_ops(ctx, rb->Format, format, type, + GL_FALSE); + /* Describe the dst format */ + dst_is_integer = _mesa_is_enum_format_integer(format); + dst_stride = _mesa_image_row_stride(packing, width, format, type); + dst_format = _mesa_format_from_format_and_type(format, type); + dst_is_luminance = format == GL_LUMINANCE || + format == GL_LUMINANCE_ALPHA || + format == GL_LUMINANCE_INTEGER_EXT || + format == GL_LUMINANCE_ALPHA_INTEGER_EXT; dst = (GLubyte *) _mesa_image_address2d(packing, pixels, width, height, - format, type, 0, 0); + format, type, 0, 0); + /* Map the source render buffer */ ctx->Driver.MapRenderbuffer(ctx, rb, x, y, width, height, GL_MAP_READ_BIT, - &map, &stride); + &map, &rb_stride); if (!map) { _mesa_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels"); - return GL_TRUE; /* don't bother trying the slow path */ + return; } + rb_format = _mesa_get_srgb_format_linear(rb->Format); - if (swizzle_rb) { - /* swap R/B */ - for (j = 0; j < height; j++) { - int i; - for (i = 0; i < width; i++) { - GLuint *dst4 = (GLuint *) dst, *map4 = (GLuint *) map; - GLuint pixel = map4[i]; - dst4[i] = (pixel & 0xff00ff00) - | ((pixel & 0x00ff0000) >> 16) - | ((pixel & 0x000000ff) << 16); - } - dst += dstStride; - map += stride; - } - } else if (copy_xrgb) { - /* convert xrgb -> argb */ - for (j = 0; j < height; j++) { - GLuint *dst4 = (GLuint *) dst, *map4 = (GLuint *) map; - int i; - for (i = 0; i < width; i++) { - dst4[i] = map4[i] | 0xff000000; /* set A=0xff */ - } - dst += dstStride; - map += stride; - } + /* + * Depending on the base formats involved in the conversion we might need to + * rebase some values, so for these formats we compute a rebase swizzle. + */ + if (rb->_BaseFormat == GL_LUMINANCE || rb->_BaseFormat == GL_INTENSITY) { + needs_rebase = true; + rebase_swizzle[0] = MESA_FORMAT_SWIZZLE_X; + rebase_swizzle[1] = MESA_FORMAT_SWIZZLE_ZERO; + rebase_swizzle[2] = MESA_FORMAT_SWIZZLE_ZERO; + rebase_swizzle[3] = MESA_FORMAT_SWIZZLE_ONE; + } else if (rb->_BaseFormat == GL_LUMINANCE_ALPHA) { + needs_rebase = true; + rebase_swizzle[0] = MESA_FORMAT_SWIZZLE_X; + rebase_swizzle[1] = MESA_FORMAT_SWIZZLE_ZERO; + rebase_swizzle[2] = MESA_FORMAT_SWIZZLE_ZERO; + rebase_swizzle[3] = MESA_FORMAT_SWIZZLE_W; + } else if (_mesa_get_format_base_format(rb_format) != rb->_BaseFormat) { + needs_rebase = + _mesa_compute_rgba2base2rgba_component_mapping(rb->_BaseFormat, + rebase_swizzle); + } else { + needs_rebase = false; } - ctx->Driver.UnmapRenderbuffer(ctx, rb); - - return GL_TRUE; -} - -static void -slow_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, - GLbitfield transferOps ) -{ - struct gl_renderbuffer *rb = ctx->ReadBuffer->_ColorReadBuffer; - const mesa_format rbFormat = _mesa_get_srgb_format_linear(rb->Format); - void *rgba; - GLubyte *dst, *map; - int dstStride, stride, j; - GLboolean dst_is_integer = _mesa_is_enum_format_integer(format); - GLboolean dst_is_uint = _mesa_is_format_unsigned(rbFormat); - - dstStride = _mesa_image_row_stride(packing, width, format, type); - dst = (GLubyte *) _mesa_image_address2d(packing, pixels, width, height, - format, type, 0, 0); - - ctx->Driver.MapRenderbuffer(ctx, rb, x, y, width, height, GL_MAP_READ_BIT, - &map, &stride); - if (!map) { - _mesa_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels"); - return; - } + /* Since _mesa_format_convert does not handle transferOps we need to handle + * them before we call the function. This requires to convert to RGBA float + * first so we can call _mesa_apply_rgba_transfer_ops. If the dst format is + * integer transferOps do not apply. + * + * Converting to luminance also requires converting to RGBA first, so we can + * then compute luminance values as L=R+G+B. Notice that this is different + * from GetTexImage, where we compute L=R. + */ + assert(!transferOps || (transferOps && !dst_is_integer)); - rgba = malloc(width * MAX_PIXEL_BYTES); - if (!rgba) - goto done; + needs_rgba = transferOps || dst_is_luminance; + rgba = NULL; + if (needs_rgba) { + uint32_t rgba_format; + int rgba_stride; + bool need_convert; - for (j = 0; j < height; j++) { + /* Convert to RGBA float or int/uint depending on the type of the src */ if (dst_is_integer) { - _mesa_unpack_uint_rgba_row(rbFormat, width, map, (GLuint (*)[4]) rgba); - _mesa_rebase_rgba_uint(width, (GLuint (*)[4]) rgba, - rb->_BaseFormat); - if (dst_is_uint) { - _mesa_pack_rgba_span_from_uints(ctx, width, (GLuint (*)[4]) rgba, format, - type, dst); + src_is_uint = _mesa_is_format_unsigned(rb_format); + if (src_is_uint) { + rgba_format = RGBA8888_UINT; + rgba_stride = width * 4 * sizeof(GLuint); } else { - _mesa_pack_rgba_span_from_ints(ctx, width, (GLint (*)[4]) rgba, format, - type, dst); + rgba_format = RGBA8888_INT; + rgba_stride = width * 4 * sizeof(GLint); } } else { - _mesa_unpack_rgba_row(rbFormat, width, map, (GLfloat (*)[4]) rgba); - _mesa_rebase_rgba_float(width, (GLfloat (*)[4]) rgba, - rb->_BaseFormat); - _mesa_pack_rgba_span_float(ctx, width, (GLfloat (*)[4]) rgba, format, - type, dst, packing, transferOps); + rgba_format = RGBA8888_FLOAT; + rgba_stride = width * 4 * sizeof(GLfloat); } - dst += dstStride; - map += stride; - } - - free(rgba); - -done: - ctx->Driver.UnmapRenderbuffer(ctx, rb); -} -/* - * 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 ) -{ - GLbitfield transferOps; - struct gl_framebuffer *fb = ctx->ReadBuffer; - struct gl_renderbuffer *rb = fb->_ColorReadBuffer; + /* If we are lucky and the dst format matches the RGBA format we need to + * convert to, then we can convert directly into the dst buffer and avoid + * the final conversion/copy from the rgba buffer to the dst buffer. + */ + if (dst_format == rgba_format) { + need_convert = false; + rgba = dst; + } else { + need_convert = true; + rgba = malloc(height * rgba_stride); + if (!rgba) { + _mesa_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels"); + goto done_unmap; + } + } - if (!rb) - return; + /* Convert to RGBA now */ + _mesa_format_convert(rgba, rgba_format, rgba_stride, + map, rb_format, rb_stride, + width, height, + needs_rebase ? rebase_swizzle : NULL); + + /* Handle transfer ops if necessary */ + if (transferOps) + _mesa_apply_rgba_transfer_ops(ctx, transferOps, width * height, rgba); + + /* If we had to rebase, we have already taken care of that */ + needs_rebase = false; + + /* If we were lucky and our RGBA conversion matches the dst format, then + * we are done. + */ + if (!need_convert) + goto done_swap; + + /* Otherwise, we need to convert from RGBA to dst next */ + src = rgba; + src_format = rgba_format; + src_stride = rgba_stride; + } else { + /* No RGBA conversion needed, convert directly to dst */ + src = map; + src_format = rb_format; + src_stride = rb_stride; + } - transferOps = get_readpixels_transfer_ops(ctx, rb->Format, format, type, - GL_FALSE); + /* Do the conversion. + * + * If the dst format is Luminance, we need to do the conversion by computing + * L=R+G+B values. + */ + if (!dst_is_luminance) { + _mesa_format_convert(dst, dst_format, dst_stride, + src, src_format, src_stride, + width, height, + needs_rebase ? rebase_swizzle : NULL); + } else if (!dst_is_integer) { + /* Compute float Luminance values from RGBA float */ + int luminance_stride, luminance_bytes; + void *luminance; + uint32_t luminance_format; + + luminance_stride = width * sizeof(GL_FLOAT); + if (format == GL_LUMINANCE_ALPHA) + luminance_stride *= 2; + luminance_bytes = height * luminance_stride; + luminance = malloc(luminance_bytes); + if (!luminance) { + _mesa_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels"); + free(rgba); + goto done_unmap; + } + _mesa_pack_luminance_from_rgba_float(width * height, src, + luminance, format, transferOps); + + /* Convert from Luminance float to dst (this will hadle type conversion + * from float to the type of dst if necessary) + */ + luminance_format = _mesa_format_from_format_and_type(format, GL_FLOAT); + _mesa_format_convert(dst, dst_format, dst_stride, + luminance, luminance_format, luminance_stride, + width, height, NULL); + } else { + _mesa_pack_luminance_from_rgba_integer(width * height, src, !src_is_uint, + dst, format, type); + } - /* Try the optimized paths first. */ - if (!transferOps && - read_rgba_pixels_swizzle(ctx, x, y, width, height, - format, type, pixels, packing)) { - return; + if (rgba) + free(rgba); + +done_swap: + /* Handle byte swapping if required */ + if (packing->SwapBytes) { + int components = _mesa_components_in_format(format); + GLint swapSize = _mesa_sizeof_packed_type(type); + if (swapSize == 2) + _mesa_swap2((GLushort *) dst, width * height * components); + else if (swapSize == 4) + _mesa_swap4((GLuint *) dst, width * height * components); } - slow_read_rgba_pixels(ctx, x, y, width, height, - format, type, pixels, packing, transferOps); +done_unmap: + ctx->Driver.UnmapRenderbuffer(ctx, rb); } /** -- 2.30.2