From 7eb8d007a502d6c6d62eab590d71f6085aef78f9 Mon Sep 17 00:00:00 2001 From: Gabe Black Date: Mon, 4 Dec 2017 20:22:43 -0800 Subject: base: Split out the pixel class in framebuffer.(cc|hh). These are really two separate things. Also, while it's realitively straightforward to write a unit test for the pixel conversion code, the framebuffer object is serializable and brings in more dependencies. Change-Id: If954caeb0bfedb1002cfb1a7a115a00c90d56d19 Reviewed-on: https://gem5-review.googlesource.com/6341 Reviewed-by: Andreas Sandberg Maintainer: Andreas Sandberg --- src/base/pixel.hh | 231 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 231 insertions(+) create mode 100644 src/base/pixel.hh (limited to 'src/base/pixel.hh') diff --git a/src/base/pixel.hh b/src/base/pixel.hh new file mode 100644 index 000000000..f6faacec6 --- /dev/null +++ b/src/base/pixel.hh @@ -0,0 +1,231 @@ +/* + * Copyright (c) 2015 ARM Limited + * All rights reserved + * + * The license below extends only to copyright in the software and shall + * not be construed as granting a license to any other intellectual + * property including but not limited to intellectual property relating + * to a hardware implementation of the functionality of the software + * licensed hereunder. You may use the software subject to the license + * terms below provided that you ensure that this notice is replicated + * unmodified and in its entirety in all distributions of the software, + * modified or unmodified, in source code or in binary form. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer; + * redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution; + * neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Authors: Andreas Sandberg + */ + +#ifndef __BASE_PIXEL_HH__ +#define __BASE_PIXEL_HH__ + +#include +#include +#include +#include + +#include "base/compiler.hh" +#include "base/cprintf.hh" +#include "base/str.hh" +#include "base/types.hh" + +/** + * Internal gem5 representation of a Pixel. + */ +struct Pixel +{ + Pixel() + : red(0), green(0), blue(0), padding(0) {} + + Pixel(uint8_t _red, uint8_t _green, uint8_t _blue) + : red(_red), green(_green), blue(_blue), padding(0) {} + + uint8_t red; + uint8_t green; + uint8_t blue; + uint8_t padding; +}; + +inline bool +operator==(const Pixel &lhs, const Pixel &rhs) +{ + return lhs.red == rhs.red && + lhs.green == rhs.green && + lhs.blue == rhs.blue && + lhs.padding == rhs.padding; +} + +/** + * Configurable RGB pixel converter. + * + * This class converts between external RGB representations and gem5's + * internal Pixel representation. The class assumes that pixels are + * stored in a word of configurable length (up to 32 bits). Individual + * pixels are assumed to be represented by contiguous bit ranges in + * the word (i.e., it is possible to shift and mask out a contiguous + * bit range for each pixel). + */ +class PixelConverter +{ + public: + /** + * Color channel conversion and scaling helper class. + */ + struct Channel { + /** + * @param offset Offset in bits. + * @param width Width in bits. + */ + Channel(unsigned offset, unsigned width); + + /** + * Get the value of a single color channel represented as an + * 8-bit number. + */ + uint8_t toPixel(uint32_t word) const { + return round(((word >> offset) & mask) * factor); + } + + /** + * Convert an 8-bit representation of a color into an external + * format. + */ + uint32_t fromPixel(uint8_t ch) const { + return (static_cast(round(ch / factor)) & mask) << offset; + } + + /** Offset in bits */ + unsigned offset; + /** Bit mask (after shifting) */ + unsigned mask; + /** + * Scaling factor when converting to the full range of an + * 8-bit color channel + */ + float factor; + }; + + PixelConverter(unsigned length, + unsigned ro, unsigned go, unsigned bo, + unsigned rw, unsigned gw, unsigned bw, + ByteOrder byte_order = LittleEndianByteOrder); + + /** Get the Pixel representation of a color word. */ + Pixel toPixel(uint32_t word) const { + return Pixel(ch_r.toPixel(word), + ch_g.toPixel(word), + ch_b.toPixel(word)); + } + + /** Get a Pixel representation by reading a word from memory. */ + Pixel toPixel(const uint8_t *rfb) const { + return toPixel(readWord(rfb)); + } + + /** Convert a Pixel into a color word */ + uint32_t fromPixel(const Pixel &pixel) const { + return ch_r.fromPixel(pixel.red) | + ch_g.fromPixel(pixel.green) | + ch_b.fromPixel(pixel.blue); + } + + /** + * Convert a pixel into a color word and store the resulting word + * in memory. + */ + void fromPixel(uint8_t *rfb, const Pixel &pixel) const { + writeWord(rfb, fromPixel(pixel)); + } + + /** + * Read a word of a given length and endianness from memory. + * + * The number of bytes read from memory is determined by the + * length of a color word. Note that some of the bytes may be + * padding. + * + * @param p Pointer to the first byte in the word. + * @return Word in host endianness. + */ + uint32_t readWord(const uint8_t *p) const; + /** + * Write a word of a given length and endianness to memory. + * + * @param p Pointer to the first byte in memory. + * @param word Word to store (host endianness). + */ + void writeWord(uint8_t *p, uint32_t word) const; + + /** Bytes per pixel when stored in memory (including padding) */ + unsigned length; + /** + * Number of bits used to represent one pixel value (excluding + * padding). This could be less than length * 8 if the pixel value + * is padded. + */ + unsigned depth; + /** Byte order when stored to memory. */ + ByteOrder byte_order; + + /** Red channel conversion helper */ + Channel ch_r; + /** Green channel conversion helper */ + Channel ch_g; + /** Blue channel conversion helper */ + Channel ch_b; + + /** Predefined 32-bit RGB (red in least significant bits, 8 + * bits/channel, little endian) conversion helper */ + static const PixelConverter rgba8888_le; + /** Predefined 16-bit RGB565 (red in least significant bits, + * little endian) conversion helper */ + static const PixelConverter rgb565_le; + + /** Predefined 32-bit RGB (red in least significant bits, 8 + * bits/channel, big endian) conversion helper */ + static const PixelConverter rgba8888_be; + /** Predefined 16-bit RGB565 (red in least significant bits, + * big endian) conversion helper */ + static const PixelConverter rgb565_be; +}; + +inline bool +to_number(const std::string &value, Pixel &retval) +{ + uint32_t num; + if (!to_number(value, num)) + return false; + + retval = PixelConverter::rgba8888_le.toPixel(num); + return true; +} + +inline std::ostream & +operator<<(std::ostream &os, const Pixel &pxl) +{ + os << csprintf("%#.08x", PixelConverter::rgba8888_le.fromPixel(pxl)); + return os; +} + +#endif // __BASE_PIXEL_HH__ -- cgit v1.2.3