Skip to content

Commit

Permalink
Speed enhancements
Browse files Browse the repository at this point in the history
  • Loading branch information
@paulrnash
paulrnash committed Oct 13, 2019
1 parent 7d928bc commit 88973d3
Show file tree
Hide file tree
Showing 2 changed files with 174 additions and 11 deletions.
175 changes: 164 additions & 11 deletions Adafruit_SPITFT.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -909,7 +909,7 @@ void Adafruit_SPITFT::setSPISpeed(uint32_t freq) {
*/
void Adafruit_SPITFT::startWrite(void) {
SPI_BEGIN_TRANSACTION();
if(_cs >= 0) SPI_CS_LOW();
SPI_CS_LOW();
}

/*!
Expand All @@ -919,7 +919,7 @@ void Adafruit_SPITFT::startWrite(void) {
for all display types; not an SPI-specific function.
*/
void Adafruit_SPITFT::endWrite(void) {
if(_cs >= 0) SPI_CS_HIGH();
SPI_CS_HIGH();
SPI_END_TRANSACTION();
}

Expand All @@ -942,7 +942,12 @@ void Adafruit_SPITFT::endWrite(void) {
void Adafruit_SPITFT::writePixel(int16_t x, int16_t y, uint16_t color) {
if((x >= 0) && (x < _width) && (y >= 0) && (y < _height)) {
setAddrWindow(x, y, 1, 1);
#if defined(__AVR__)
AVR_WRITESPI((uint8_t)(color >> 8));
AVR_WRITESPI((uint8_t)(color));
#else
SPI_WRITE16(color);
#endif
}
}

Expand Down Expand Up @@ -1097,6 +1102,89 @@ void Adafruit_SPITFT::dmaWait(void) {
#endif
}

#define USE_FAST_FILLS
#if !defined(USE_FAST_FILLS)

inline void Adafruit_SPITFT::writeColorFast(uint16_t color, uint32_t len) { writeColor(color, len); }
inline void Adafruit_SPITFT::writeColorFastSmall(uint16_t color, uint16_t len) { writeColor(color, len); }

#else

void Adafruit_SPITFT::writeColorFast(uint16_t color, uint32_t len) {
#if defined(__AVR__)

#define WRITE_COLOR_LOOP_UNROLL 4
uint8_t hi = color >> 8, lo = color;

uint16_t hiloop_cnt = len / (256 * WRITE_COLOR_LOOP_UNROLL);
uint8_t tail_loops, unrolled_loops;

len -= ((uint32_t)hiloop_cnt * 256 * WRITE_COLOR_LOOP_UNROLL);
tail_loops = (uint8_t)(len / WRITE_COLOR_LOOP_UNROLL);
len -= (uint32_t)tail_loops * WRITE_COLOR_LOOP_UNROLL;

uint16_t hloop = hiloop_cnt;

do {
if (hloop) {
unrolled_loops = 255;
hloop--;
} else {
unrolled_loops = tail_loops;
}

do {
AVR_WRITESPI(hi);
AVR_WRITESPI(lo);
AVR_WRITESPI(hi);
AVR_WRITESPI(lo);
AVR_WRITESPI(hi);
AVR_WRITESPI(lo);
AVR_WRITESPI(hi);
AVR_WRITESPI(lo);
} while (unrolled_loops--);
} while (hloop);

for (uint8_t a = len; a > 0; a--) {
AVR_WRITESPI(hi);
AVR_WRITESPI(lo);
}
#else
writeColor(color, len);
#endif
}

void Adafruit_SPITFT::writeColorFastSmall(uint16_t color, uint16_t len) {
#if defined(__AVR__)

#define WRITE_COLOR_LOOP_UNROLL 4
uint8_t hi = color >> 8, lo = color;

uint8_t tail_loops = (uint8_t)(len / WRITE_COLOR_LOOP_UNROLL);
len -= (uint16_t)tail_loops * WRITE_COLOR_LOOP_UNROLL;

do {
AVR_WRITESPI(hi);
AVR_WRITESPI(lo);
AVR_WRITESPI(hi);
AVR_WRITESPI(lo);
AVR_WRITESPI(hi);
AVR_WRITESPI(lo);
AVR_WRITESPI(hi);
AVR_WRITESPI(lo);
} while (tail_loops--);

for (uint8_t a = len; a > 0; a--) {
AVR_WRITESPI(hi);
AVR_WRITESPI(lo);
}
#else
writeColor(color, len);
#endif
}

#endif // USE_FAST_FILLS

/*!
@brief Issue a series of pixels, all the same color. Not self-
contained; should follow startWrite() and setAddrWindow() calls.
Expand Down Expand Up @@ -1386,6 +1474,44 @@ void Adafruit_SPITFT::writeFillRect(int16_t x, int16_t y,
}
}

/*!
@brief Draw a filled rectangle to the display. Not self-contained;
should follow startWrite(). Typically used by higher-level
graphics primitives; user code shouldn't need to call this and
is likely to use the self-contained fillRect() instead.
writeFillRect() performs its own edge clipping and rejection;
see writeFillRectPreclipped() for a more 'raw' implementation.
@param x Horizontal position of first corner.
@param y Vertical position of first corner.
@param w Rectangle width in pixels.
@param h Rectangle height in pixels.
@param color 16-bit fill color in '565' RGB format.
@note Written in this deep-nested way because C by definition will
optimize for the 'if' case, not the 'else' -- avoids branches
and rejects clipped rectangles at the least-work possibility.
*/
void Adafruit_SPITFT::writeFillRectSmall(int16_t x, int16_t y,
uint8_t w, uint8_t h, uint16_t color) {
if(w && h) { // Nonzero width and height?
if(x < _width) { // Not off right
if(y < _height) { // Not off bottom
int16_t x2 = x + w - 1;
if(x2 >= 0) { // Not off left
int16_t y2 = y + h - 1;
if(y2 >= 0) { // Not off top
// Rectangle partly or fully overlaps screen
if(x < 0) { x = 0; w = x2 + 1; } // Clip left
if(y < 0) { y = 0; h = y2 + 1; } // Clip top
if(x2 >= _width) { w = _width - x; } // Clip right
if(y2 >= _height) { h = _height - y; } // Clip bottom
writeFillRectSmallPreclipped(x, y, w, h, color);
}
}
}
}
}
}

/*!
@brief Draw a horizontal line on the display. Performs edge clipping
and rejection. Not self-contained; should follow startWrite().
Expand All @@ -1411,7 +1537,7 @@ void inline Adafruit_SPITFT::writeFastHLine(int16_t x, int16_t y, int16_t w,
// Line partly or fully overlaps screen
if(x < 0) { x = 0; w = x2 + 1; } // Clip left
if(x2 >= _width) { w = _width - x; } // Clip right
writeFillRectPreclipped(x, y, w, 1, color);
writeFillRectSmallPreclipped(x, y, w, 1, color);
}
}
}
Expand Down Expand Up @@ -1442,7 +1568,7 @@ void inline Adafruit_SPITFT::writeFastVLine(int16_t x, int16_t y, int16_t h,
// Line partly or fully overlaps screen
if(y < 0) { y = 0; h = y2 + 1; } // Clip top
if(y2 >= _height) { h = _height - y; } // Clip bottom
writeFillRectPreclipped(x, y, 1, h, color);
writeFillRectSmallPreclipped(x, y, 1, h, color);
}
}
}
Expand Down Expand Up @@ -1471,7 +1597,34 @@ void inline Adafruit_SPITFT::writeFastVLine(int16_t x, int16_t y, int16_t h,
inline void Adafruit_SPITFT::writeFillRectPreclipped(int16_t x, int16_t y,
int16_t w, int16_t h, uint16_t color) {
setAddrWindow(x, y, w, h);
writeColor(color, (uint32_t)w * h);
writeColorFast(color, (uint32_t)w * h);
}


/*!
@brief A lower-level version of writeFillRectSmall(). This version requires
all inputs are in-bounds, that width and height are positive,
and no part extends offscreen. NO EDGE CLIPPING OR REJECTION IS
PERFORMED. If higher-level graphics primitives are written to
handle their own clipping earlier in the drawing process, this
can avoid unnecessary function calls and repeated clipping
operations in the lower-level functions.
@param x Horizontal position of first corner. MUST BE WITHIN
SCREEN BOUNDS.
@param y Vertical position of first corner. MUST BE WITHIN SCREEN
BOUNDS.
@param w Rectangle width in pixels. MUST BE POSITIVE AND NOT
EXTEND OFF SCREEN.
@param h Rectangle height in pixels. MUST BE POSITIVE AND NOT
EXTEND OFF SCREEN.
@param color 16-bit fill color in '565' RGB format.
@note This is a new function, no graphics primitives besides rects
and horizontal/vertical lines are written to best use this yet.
*/
inline void Adafruit_SPITFT::writeFillRectSmallPreclipped(int16_t x, int16_t y,
uint8_t w, uint8_t h, uint16_t color) {
setAddrWindow(x, y, w, h);
writeColorFastSmall(color, (uint16_t)w * h);
}


Expand Down Expand Up @@ -1584,7 +1737,7 @@ void Adafruit_SPITFT::drawFastHLine(int16_t x, int16_t y, int16_t w,
if(x < 0) { x = 0; w = x2 + 1; } // Clip left
if(x2 >= _width) { w = _width - x; } // Clip right
startWrite();
writeFillRectPreclipped(x, y, w, 1, color);
writeFillRectSmallPreclipped(x, y, w, 1, color);
endWrite();
}
}
Expand Down Expand Up @@ -1620,7 +1773,7 @@ void Adafruit_SPITFT::drawFastVLine(int16_t x, int16_t y, int16_t h,
if(y < 0) { y = 0; h = y2 + 1; } // Clip top
if(y2 >= _height) { h = _height - y; } // Clip bottom
startWrite();
writeFillRectPreclipped(x, y, 1, h, color);
writeFillRectSmallPreclipped(x, y, 1, h, color);
endWrite();
}
}
Expand Down Expand Up @@ -1727,7 +1880,7 @@ uint16_t Adafruit_SPITFT::color565(uint8_t red, uint8_t green, uint8_t blue) {
*/
void Adafruit_SPITFT::sendCommand(uint8_t commandByte, uint8_t *dataBytes, uint8_t numDataBytes) {
SPI_BEGIN_TRANSACTION();
if(_cs >= 0) SPI_CS_LOW();
SPI_CS_LOW();

SPI_DC_LOW(); // Command mode
spiWrite(commandByte); // Send the command byte
Expand All @@ -1738,7 +1891,7 @@ void Adafruit_SPITFT::sendCommand(uint8_t commandByte, uint8_t *dataBytes, uint8
dataBytes++;
}

if(_cs >= 0) SPI_CS_HIGH();
SPI_CS_HIGH();
SPI_END_TRANSACTION();
}

Expand All @@ -1750,7 +1903,7 @@ void Adafruit_SPITFT::sendCommand(uint8_t commandByte, uint8_t *dataBytes, uint8
*/
void Adafruit_SPITFT::sendCommand(uint8_t commandByte, const uint8_t *dataBytes, uint8_t numDataBytes) {
SPI_BEGIN_TRANSACTION();
if(_cs >= 0) SPI_CS_LOW();
SPI_CS_LOW();

SPI_DC_LOW(); // Command mode
spiWrite(commandByte); // Send the command byte
Expand All @@ -1760,7 +1913,7 @@ void Adafruit_SPITFT::sendCommand(uint8_t commandByte, const uint8_t *dataBytes,
spiWrite(pgm_read_byte(dataBytes++)); // Send the data bytes
}

if(_cs >= 0) SPI_CS_HIGH();
SPI_CS_HIGH();
SPI_END_TRANSACTION();
}

Expand Down
10 changes: 10 additions & 0 deletions Adafruit_SPITFT.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -30,6 +30,7 @@
#if defined(__AVR__)
typedef uint8_t ADAGFX_PORT_t; ///< PORT values are 8-bit
#define USE_FAST_PINIO ///< Use direct PORT register access
#define USE_FAST_FILLS
#elif defined(ARDUINO_STM32_FEATHER) // WICED
typedef class HardwareSPI SPIClass; ///< SPI is a bit odd on WICED
typedef uint32_t ADAGFX_PORT_t; ///< PORT values are 32-bit
Expand Down Expand Up @@ -226,6 +227,15 @@ class Adafruit_SPITFT : public Adafruit_GFX {
// writePixels() variant.
void dmaWait(void);

// These functions trade code space for speed by unrolling loops and using
// smaller counter vars. Speedups range from 8-24% faster.
void writeColorFast(uint16_t color, uint32_t len);
void writeColorFastSmall(uint16_t color, uint16_t len);
void writeFillRectSmall(int16_t x, int16_t y, uint8_t w, uint8_t h,
uint16_t color);
inline void writeFillRectSmallPreclipped(int16_t x, int16_t y,
uint8_t w, uint8_t h, uint16_t color);


// These functions are similar to the 'write' functions above, but with
// a chip-select and/or SPI transaction built-in. They're typically used
Expand Down

0 comments on commit 88973d3

Please sign in to comment.