I have made some performance tweaks to the library, latest version is on GitHub.
With a stock 320x240 display the NodeMCU can now execute all the timed "graphicstest" functions in 0.91s (totalled) and a compatible UTFT_Demo finishes in 0.92s.
Considering these NodeMCU boards sell for only $3 (and have Wifi built in) they are exceptional value if a small powerful processor with wireless connectivity is needed. As they operate at 3.3V they can be wired straight to the display. Typically the backlight LED benefits from the extra brightness if powered driven from 5V. (Note: some variants of the NodeMCU provide the USB 5V on the Vin pin which is handy).
I have a higher performance ESP32 on order so when the Adruino core libraries are in place for that chip I will see if I can adapt the code for that 240MHz processor though the performance is more dominated by the SPI frequency than the CPU frequency and 80MHz is the limit with the 2.2" ILI9341 display I have.
These are the times reported by the "graphicstest" for different CPU and SPI frequencies:
CPU 160MHz, SPI 80MHz
Benchmark Time (microseconds)
Screen fill 81880
Text 17484
Lines 110823
Horiz/Vert Lines 8784
Rectangles (outline) 6683
Rectangles (filled) 168311
Circles (filled) 79768
Circles (outline) 65434
Triangles (outline) 25870
Triangles (filled) 100298
Rounded rects (outline) 30082
Rounded rects (filled) 212347
Done! Total = 0.907055 s
CPU 80MHz, SPI 80MHz
Benchmark Time (microseconds)
Screen fill 82850
Text 26730
Lines 162672
Horiz/Vert Lines 10251
Rectangles (outline) 8617
Rectangles (filled) 170695
Circles (filled) 121724
Circles (outline) 97799
Triangles (outline) 37727
Triangles (filled) 137253
Rounded rects (outline) 43787
Rounded rects (filled) 236197
Done! Total = 1.135728 s
CPU 160MHz, SPI 40MHz
Benchmark Time (microseconds)
Screen fill 157817
Text 20258
Lines 130615
Horiz/Vert Lines 15264
Rectangles (outline) 10667
Rectangles (filled) 323955
Circles (filled) 100700
Circles (outline) 74626
Triangles (outline) 30953
Triangles (filled) 151077
Rounded rects (outline) 36637
Rounded rects (filled) 384025
Done! Total = 1.435837 s
80MHz, 40MHz SPI
Benchmark Time (microseconds)
Screen fill 161944
Text 29219
Lines 179507
Horiz/Vert Lines 16988
Rectangles (outline) 12709
Rectangles (filled) 332815
Circles (filled) 142200
Circles (outline) 106428
Triangles (outline) 42014
Triangles (filled) 189318
Rounded rects (outline) 50262
Rounded rects (filled) 414494
Done! Total = 1.677213 s
160MHz, 20MHz SPI
Benchmark Time (microseconds)
Screen fill 312993
Text 26787
Lines 173766
Horiz/Vert Lines 28570
Rectangles (outline) 18852
Rectangles (filled) 642021
Circles (filled) 145685
Circles (outline) 98588
Triangles (outline) 41397
Triangles (filled) 255954
Rounded rects (outline) 52092
Rounded rects (filled) 735513
Done! Total = 2.531470 s
80MHz, 20MHz SPI
Benchmark Time (microseconds)
Screen fill 315007
Text 35582
Lines 221512
Horiz/Vert Lines 30092
Rectangles (outline) 20778
Rectangles (filled) 646544
Circles (filled) 186471
Circles (outline) 129292
Triangles (outline) 52337
Triangles (filled) 292740
Rounded rects (outline) 65204
Rounded rects (filled) 761167
Done! Total = 2.756191 s