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Diffstat (limited to 'src/base/framebuffer.hh')
| -rw-r--r-- | src/base/framebuffer.hh | 355 |
1 files changed, 355 insertions, 0 deletions
diff --git a/src/base/framebuffer.hh b/src/base/framebuffer.hh new file mode 100644 index 000000000..457c6d06d --- /dev/null +++ b/src/base/framebuffer.hh @@ -0,0 +1,355 @@ +/* + * 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_FRAMEBUFFER_HH__ +#define __BASE_FRAMEBUFFER_HH__ + +#include <cmath> +#include <cstdint> + +#include <vector> + +#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<uint8_t>(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; +}; + +/** + * Internal gem5 representation of a frame buffer + * + * Display controllers and other devices producing images are expected + * to use this class to represent the final image. + * + * Pixels are indexed relative to the upper left corner of the + * image. That is, the pixel at position (0, 0) is the upper left + * corner. The backing store is a linear vector of Pixels ordered left + * to right starting in the upper left corner. + */ +class FrameBuffer +{ + public: + /** + * Create a frame buffer of a given size. + * + * @param width Width in pixels + * @param height Height in pixels + */ + FrameBuffer(unsigned width, unsigned height); + /** Create an empty (0x0) frame buffer */ + FrameBuffer(); + + virtual ~FrameBuffer(); + + /** + * Resize the frame buffer. + * + * This method resizes frame buffer including the backing + * store. The contents of the backing store are undefined after + * this operation. + * + * @param with Width in pixels. + * @param height Height in pixels. + */ + void resize(unsigned width, unsigned height); + + /** Frame buffer width in pixels */ + unsigned width() const { return _width; } + /** Frame buffer height in pixels */ + unsigned height() const { return _height; } + /** Total number of pixels in frame buffer */ + unsigned area() const { return _width * _height; } + + /** + * Fill the frame buffer with a single pixel value + * + * @param pixel Pixel value to fill with. + */ + void fill(const Pixel &pixel); + /** + * Fill the frame buffer with black pixels + */ + void clear(); + + /** + * Fill the frame buffer with pixel data from an external buffer + * of the same width and height as this frame buffer. + * + * @param fb External frame buffer + * @param conv Pixel conversion helper + */ + void copyIn(const uint8_t *fb, const PixelConverter &conv); + /** + * Fill the frame buffer with pixel data from an external buffer + * of the same width and height as this frame buffer. + * + * @param fb External frame buffer + * @param conv Pixel conversion helper + */ + void copyIn(const std::vector<uint8_t> &fb, const PixelConverter &conv) { + copyIn(fb.data(), conv); + } + + /** + * Store the contents of this frame buffer in an external buffer + * of the same width and height as this frame buffer. + * + * @param fb External frame buffer + * @param conv Pixel conversion helper + */ + void copyOut(uint8_t *fb, const PixelConverter &conv) const; + /** + * Store the contents of this frame buffer in an external buffer + * of the same width and height as this frame buffer. + * + * @param fb External frame buffer + * @param conv Pixel conversion helper + */ + void copyOut(std::vector<uint8_t> &fb, const PixelConverter &conv) const { + copyOut(fb.data(), conv); + } + + /** + * Get a pixel from an (x, y) coordinate + * + * @param x Distance from the left margin. + * @param y Distance from the top of the frame. + */ + const Pixel &pixel(unsigned x, unsigned y) const { + assert(x < _width); + assert(y < _height); + + return pixels[y * _width + x]; + } + + /** + * Get a pixel from an (x, y) coordinate + * + * @param x Distance from the left margin. + * @param y Distance from the top of the frame. + */ + Pixel &pixel(unsigned x, unsigned y) { + assert(x < _width); + assert(y < _height); + + return pixels[y * _width + x]; + } + + /** + * Create a hash of the image that can be used for quick + * comparisons. + */ + uint64_t getHash() const; + + /** + * Static "dummy" frame buffer. + * + * This is a dummy frame buffer that can be used as a place holder + * for devices that always expect a frame buffer to be present. + */ + static const FrameBuffer dummy; + + /** Frame buffer backing store */ + std::vector<Pixel> pixels; + + protected: + /** Width in pixels */ + unsigned _width; + /** Height in pixels */ + unsigned _height; +}; + +#endif // __BASE_FRAMEBUFFER_HH__ |