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	* RGB Matrix overhaul Breakout of animations to separate files Integration of optimized int based math lib Overhaul of rgb_matrix.c and animations for performance * Updating effect function api for future extensions * Combined the keypresses || keyreleases define checks into a single define so I stop forgetting it where necessary * Moving define RGB_MATRIX_KEYREACTIVE_ENABLED earlier in the include chain
		
			
				
	
	
		
			543 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			543 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
#ifndef __INC_LIB8TION_SCALE_H
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#define __INC_LIB8TION_SCALE_H
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///@ingroup lib8tion
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///@defgroup Scaling Scaling functions
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/// Fast, efficient 8-bit scaling functions specifically
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/// designed for high-performance LED programming.
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///
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/// Because of the AVR(Arduino) and ARM assembly language
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/// implementations provided, using these functions often
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/// results in smaller and faster code than the equivalent
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/// program using plain "C" arithmetic and logic.
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///@{
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///  scale one byte by a second one, which is treated as
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///  the numerator of a fraction whose denominator is 256
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///  In other words, it computes i * (scale / 256)
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///  4 clocks AVR with MUL, 2 clocks ARM
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LIB8STATIC_ALWAYS_INLINE uint8_t scale8( uint8_t i, fract8 scale)
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{
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#if SCALE8_C == 1
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#if (FASTLED_SCALE8_FIXED == 1)
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    return (((uint16_t)i) * (1+(uint16_t)(scale))) >> 8;
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#else
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    return ((uint16_t)i * (uint16_t)(scale) ) >> 8;
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#endif
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#elif SCALE8_AVRASM == 1
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#if defined(LIB8_ATTINY)
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#if (FASTLED_SCALE8_FIXED == 1)
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    uint8_t work=i;
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#else
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    uint8_t work=0;
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#endif
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    uint8_t cnt=0x80;
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    asm volatile(
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#if (FASTLED_SCALE8_FIXED == 1)
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        "  inc %[scale]                 \n\t"
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        "  breq DONE_%=                 \n\t"
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        "  clr %[work]                  \n\t"
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#endif
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        "LOOP_%=:                       \n\t"
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        /*"  sbrc %[scale], 0             \n\t"
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        "  add %[work], %[i]            \n\t"
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        "  ror %[work]                  \n\t"
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        "  lsr %[scale]                 \n\t"
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        "  clc                          \n\t"*/
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        "  sbrc %[scale], 0             \n\t"
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        "  add %[work], %[i]            \n\t"
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        "  ror %[work]                  \n\t"
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        "  lsr %[scale]                 \n\t"
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        "  lsr %[cnt]                   \n\t"
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        "brcc LOOP_%=                   \n\t"
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        "DONE_%=:                       \n\t"
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        : [work] "+r" (work), [cnt] "+r" (cnt)
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        : [scale] "r" (scale), [i] "r" (i)
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        :
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      );
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    return work;
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#else
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    asm volatile(
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#if (FASTLED_SCALE8_FIXED==1)
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        // Multiply 8-bit i * 8-bit scale, giving 16-bit r1,r0
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        "mul %0, %1          \n\t"
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        // Add i to r0, possibly setting the carry flag
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        "add r0, %0         \n\t"
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        // load the immediate 0 into i (note, this does _not_ touch any flags)
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        "ldi %0, 0x00       \n\t"
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        // walk and chew gum at the same time
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        "adc %0, r1          \n\t"
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#else
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         /* Multiply 8-bit i * 8-bit scale, giving 16-bit r1,r0 */
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         "mul %0, %1          \n\t"
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         /* Move the high 8-bits of the product (r1) back to i */
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         "mov %0, r1          \n\t"
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         /* Restore r1 to "0"; it's expected to always be that */
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#endif
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         "clr __zero_reg__    \n\t"
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         : "+a" (i)      /* writes to i */
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         : "a"  (scale)  /* uses scale */
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         : "r0", "r1"    /* clobbers r0, r1 */ );
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    /* Return the result */
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    return i;
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#endif
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#else
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#error "No implementation for scale8 available."
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#endif
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}
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///  The "video" version of scale8 guarantees that the output will
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///  be only be zero if one or both of the inputs are zero.  If both
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///  inputs are non-zero, the output is guaranteed to be non-zero.
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///  This makes for better 'video'/LED dimming, at the cost of
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///  several additional cycles.
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LIB8STATIC_ALWAYS_INLINE uint8_t scale8_video( uint8_t i, fract8 scale)
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{
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#if SCALE8_C == 1 || defined(LIB8_ATTINY)
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    uint8_t j = (((int)i * (int)scale) >> 8) + ((i&&scale)?1:0);
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    // uint8_t nonzeroscale = (scale != 0) ? 1 : 0;
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    // uint8_t j = (i == 0) ? 0 : (((int)i * (int)(scale) ) >> 8) + nonzeroscale;
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    return j;
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#elif SCALE8_AVRASM == 1
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    uint8_t j=0;
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    asm volatile(
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        "  tst %[i]\n\t"
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        "  breq L_%=\n\t"
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        "  mul %[i], %[scale]\n\t"
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        "  mov %[j], r1\n\t"
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        "  clr __zero_reg__\n\t"
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        "  cpse %[scale], r1\n\t"
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        "  subi %[j], 0xFF\n\t"
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        "L_%=: \n\t"
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        : [j] "+a" (j)
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        : [i] "a" (i), [scale] "a" (scale)
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        : "r0", "r1");
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    return j;
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    // uint8_t nonzeroscale = (scale != 0) ? 1 : 0;
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    // asm volatile(
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    //      "      tst %0           \n"
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    //      "      breq L_%=        \n"
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    //      "      mul %0, %1       \n"
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    //      "      mov %0, r1       \n"
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    //      "      add %0, %2       \n"
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    //      "      clr __zero_reg__ \n"
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    //      "L_%=:                  \n"
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    //      : "+a" (i)
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    //      : "a" (scale), "a" (nonzeroscale)
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    //      : "r0", "r1");
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    // // Return the result
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    // return i;
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#else
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#error "No implementation for scale8_video available."
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#endif
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}
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/// This version of scale8 does not clean up the R1 register on AVR
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/// If you are doing several 'scale8's in a row, use this, and
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/// then explicitly call cleanup_R1.
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LIB8STATIC_ALWAYS_INLINE uint8_t scale8_LEAVING_R1_DIRTY( uint8_t i, fract8 scale)
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{
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#if SCALE8_C == 1
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#if (FASTLED_SCALE8_FIXED == 1)
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    return (((uint16_t)i) * ((uint16_t)(scale)+1)) >> 8;
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#else
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    return ((int)i * (int)(scale) ) >> 8;
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#endif
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#elif SCALE8_AVRASM == 1
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    asm volatile(
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      #if (FASTLED_SCALE8_FIXED==1)
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              // Multiply 8-bit i * 8-bit scale, giving 16-bit r1,r0
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              "mul %0, %1          \n\t"
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              // Add i to r0, possibly setting the carry flag
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              "add r0, %0         \n\t"
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              // load the immediate 0 into i (note, this does _not_ touch any flags)
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              "ldi %0, 0x00       \n\t"
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              // walk and chew gum at the same time
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              "adc %0, r1          \n\t"
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      #else
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         /* Multiply 8-bit i * 8-bit scale, giving 16-bit r1,r0 */
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         "mul %0, %1    \n\t"
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         /* Move the high 8-bits of the product (r1) back to i */
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         "mov %0, r1    \n\t"
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      #endif
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         /* R1 IS LEFT DIRTY HERE; YOU MUST ZERO IT OUT YOURSELF  */
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         /* "clr __zero_reg__    \n\t" */
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         : "+a" (i)      /* writes to i */
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         : "a"  (scale)  /* uses scale */
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         : "r0", "r1"    /* clobbers r0, r1 */ );
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    // Return the result
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    return i;
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#else
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#error "No implementation for scale8_LEAVING_R1_DIRTY available."
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#endif
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}
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/// This version of scale8_video does not clean up the R1 register on AVR
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/// If you are doing several 'scale8_video's in a row, use this, and
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/// then explicitly call cleanup_R1.
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LIB8STATIC_ALWAYS_INLINE uint8_t scale8_video_LEAVING_R1_DIRTY( uint8_t i, fract8 scale)
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{
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#if SCALE8_C == 1 || defined(LIB8_ATTINY)
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    uint8_t j = (((int)i * (int)scale) >> 8) + ((i&&scale)?1:0);
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    // uint8_t nonzeroscale = (scale != 0) ? 1 : 0;
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    // uint8_t j = (i == 0) ? 0 : (((int)i * (int)(scale) ) >> 8) + nonzeroscale;
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    return j;
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#elif SCALE8_AVRASM == 1
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    uint8_t j=0;
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    asm volatile(
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        "  tst %[i]\n\t"
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        "  breq L_%=\n\t"
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        "  mul %[i], %[scale]\n\t"
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        "  mov %[j], r1\n\t"
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        "  breq L_%=\n\t"
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        "  subi %[j], 0xFF\n\t"
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        "L_%=: \n\t"
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        : [j] "+a" (j)
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        : [i] "a" (i), [scale] "a" (scale)
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        : "r0", "r1");
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    return j;
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    // uint8_t nonzeroscale = (scale != 0) ? 1 : 0;
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    // asm volatile(
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    //      "      tst %0           \n"
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    //      "      breq L_%=        \n"
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    //      "      mul %0, %1       \n"
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    //      "      mov %0, r1       \n"
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    //      "      add %0, %2       \n"
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    //      "      clr __zero_reg__ \n"
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    //      "L_%=:                  \n"
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    //      : "+a" (i)
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    //      : "a" (scale), "a" (nonzeroscale)
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    //      : "r0", "r1");
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    // // Return the result
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    // return i;
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#else
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#error "No implementation for scale8_video_LEAVING_R1_DIRTY available."
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#endif
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}
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/// Clean up the r1 register after a series of *LEAVING_R1_DIRTY calls
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LIB8STATIC_ALWAYS_INLINE void cleanup_R1(void)
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{
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#if CLEANUP_R1_AVRASM == 1
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    // Restore r1 to "0"; it's expected to always be that
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    asm volatile( "clr __zero_reg__  \n\t" : : : "r1" );
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#endif
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}
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/// scale a 16-bit unsigned value by an 8-bit value,
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///         considered as numerator of a fraction whose denominator
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///         is 256. In other words, it computes i * (scale / 256)
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LIB8STATIC_ALWAYS_INLINE uint16_t scale16by8( uint16_t i, fract8 scale )
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{
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#if SCALE16BY8_C == 1
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    uint16_t result;
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#if FASTLED_SCALE8_FIXED == 1
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    result = (i * (1+((uint16_t)scale))) >> 8;
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#else
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    result = (i * scale) / 256;
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#endif
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    return result;
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#elif SCALE16BY8_AVRASM == 1
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#if FASTLED_SCALE8_FIXED == 1
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    uint16_t result = 0;
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    asm volatile(
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                 // result.A = HighByte( (i.A x scale) + i.A )
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                 "  mul %A[i], %[scale]                 \n\t"
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                 "  add r0, %A[i]                       \n\t"
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            //   "  adc r1, [zero]                      \n\t"
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            //   "  mov %A[result], r1                  \n\t"
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                 "  adc %A[result], r1                  \n\t"
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                 // result.A-B += i.B x scale
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                 "  mul %B[i], %[scale]                 \n\t"
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                 "  add %A[result], r0                  \n\t"
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                 "  adc %B[result], r1                  \n\t"
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                 // cleanup r1
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                 "  clr __zero_reg__                    \n\t"
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                 // result.A-B += i.B
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                 "  add %A[result], %B[i]               \n\t"
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                 "  adc %B[result], __zero_reg__        \n\t"
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                 : [result] "+r" (result)
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                 : [i] "r" (i), [scale] "r" (scale)
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                 : "r0", "r1"
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                 );
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    return result;
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#else
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    uint16_t result = 0;
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    asm volatile(
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         // result.A = HighByte(i.A x j )
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         "  mul %A[i], %[scale]                 \n\t"
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         "  mov %A[result], r1                  \n\t"
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         //"  clr %B[result]                      \n\t"
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         // result.A-B += i.B x j
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         "  mul %B[i], %[scale]                 \n\t"
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         "  add %A[result], r0                  \n\t"
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         "  adc %B[result], r1                  \n\t"
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         // cleanup r1
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         "  clr __zero_reg__                    \n\t"
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         : [result] "+r" (result)
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         : [i] "r" (i), [scale] "r" (scale)
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         : "r0", "r1"
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         );
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    return result;
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#endif
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#else
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    #error "No implementation for scale16by8 available."
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#endif
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}
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/// scale a 16-bit unsigned value by a 16-bit value,
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///         considered as numerator of a fraction whose denominator
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///         is 65536. In other words, it computes i * (scale / 65536)
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LIB8STATIC uint16_t scale16( uint16_t i, fract16 scale )
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{
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  #if SCALE16_C == 1
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    uint16_t result;
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#if FASTLED_SCALE8_FIXED == 1
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    result = ((uint32_t)(i) * (1+(uint32_t)(scale))) / 65536;
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#else
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    result = ((uint32_t)(i) * (uint32_t)(scale)) / 65536;
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#endif
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    return result;
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#elif SCALE16_AVRASM == 1
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#if FASTLED_SCALE8_FIXED == 1
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    // implemented sort of like
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    //   result = ((i * scale) + i ) / 65536
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    //
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    // why not like this, you may ask?
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    //   result = (i * (scale+1)) / 65536
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    // the answer is that if scale is 65535, then scale+1
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    // will be zero, which is not what we want.
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    uint32_t result;
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    asm volatile(
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                 // result.A-B  = i.A x scale.A
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                 "  mul %A[i], %A[scale]                 \n\t"
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                 //  save results...
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                 // basic idea:
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                 //"  mov %A[result], r0                 \n\t"
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                 //"  mov %B[result], r1                 \n\t"
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                 // which can be written as...
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                 "  movw %A[result], r0                   \n\t"
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                 // Because we're going to add i.A-B to
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                 // result.A-D, we DO need to keep both
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                 // the r0 and r1 portions of the product
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                 // UNlike in the 'unfixed scale8' version.
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                 // So the movw here is needed.
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                 : [result] "=r" (result)
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                 : [i] "r" (i),
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                 [scale] "r" (scale)
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                 : "r0", "r1"
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                 );
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    asm volatile(
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                 // result.C-D  = i.B x scale.B
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                 "  mul %B[i], %B[scale]                 \n\t"
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                 //"  mov %C[result], r0                 \n\t"
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                 //"  mov %D[result], r1                 \n\t"
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                 "  movw %C[result], r0                   \n\t"
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                 : [result] "+r" (result)
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                 : [i] "r" (i),
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                 [scale] "r" (scale)
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                 : "r0", "r1"
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                 );
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    const uint8_t  zero = 0;
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    asm volatile(
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                 // result.B-D += i.B x scale.A
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                 "  mul %B[i], %A[scale]                 \n\t"
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                 "  add %B[result], r0                   \n\t"
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                 "  adc %C[result], r1                   \n\t"
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                 "  adc %D[result], %[zero]              \n\t"
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                 // result.B-D += i.A x scale.B
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                 "  mul %A[i], %B[scale]                 \n\t"
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                 "  add %B[result], r0                   \n\t"
 | 
						|
                 "  adc %C[result], r1                   \n\t"
 | 
						|
                 "  adc %D[result], %[zero]              \n\t"
 | 
						|
 | 
						|
                 // cleanup r1
 | 
						|
                 "  clr r1                               \n\t"
 | 
						|
 | 
						|
                 : [result] "+r" (result)
 | 
						|
                 : [i] "r" (i),
 | 
						|
                 [scale] "r" (scale),
 | 
						|
                 [zero] "r" (zero)
 | 
						|
                 : "r0", "r1"
 | 
						|
                 );
 | 
						|
 | 
						|
    asm volatile(
 | 
						|
                 // result.A-D += i.A-B
 | 
						|
                 "  add %A[result], %A[i]                \n\t"
 | 
						|
                 "  adc %B[result], %B[i]                \n\t"
 | 
						|
                 "  adc %C[result], %[zero]              \n\t"
 | 
						|
                 "  adc %D[result], %[zero]              \n\t"
 | 
						|
                 : [result] "+r" (result)
 | 
						|
                 : [i] "r" (i),
 | 
						|
                 [zero] "r" (zero)
 | 
						|
                 );
 | 
						|
 | 
						|
    result = result >> 16;
 | 
						|
    return result;
 | 
						|
#else
 | 
						|
    uint32_t result;
 | 
						|
    asm volatile(
 | 
						|
                 // result.A-B  = i.A x scale.A
 | 
						|
                 "  mul %A[i], %A[scale]                 \n\t"
 | 
						|
                 //  save results...
 | 
						|
                 // basic idea:
 | 
						|
                 //"  mov %A[result], r0                 \n\t"
 | 
						|
                 //"  mov %B[result], r1                 \n\t"
 | 
						|
                 // which can be written as...
 | 
						|
                 "  movw %A[result], r0                   \n\t"
 | 
						|
                 // We actually don't need to do anything with r0,
 | 
						|
                 // as result.A is never used again here, so we
 | 
						|
                 // could just move the high byte, but movw is
 | 
						|
                 // one clock cycle, just like mov, so might as
 | 
						|
                 // well, in case we want to use this code for
 | 
						|
                 // a generic 16x16 multiply somewhere.
 | 
						|
 | 
						|
                 : [result] "=r" (result)
 | 
						|
                 : [i] "r" (i),
 | 
						|
                   [scale] "r" (scale)
 | 
						|
                 : "r0", "r1"
 | 
						|
                 );
 | 
						|
 | 
						|
    asm volatile(
 | 
						|
                 // result.C-D  = i.B x scale.B
 | 
						|
                 "  mul %B[i], %B[scale]                 \n\t"
 | 
						|
                 //"  mov %C[result], r0                 \n\t"
 | 
						|
                 //"  mov %D[result], r1                 \n\t"
 | 
						|
                 "  movw %C[result], r0                   \n\t"
 | 
						|
                 : [result] "+r" (result)
 | 
						|
                 : [i] "r" (i),
 | 
						|
                   [scale] "r" (scale)
 | 
						|
                 : "r0", "r1"
 | 
						|
                 );
 | 
						|
 | 
						|
    const uint8_t  zero = 0;
 | 
						|
    asm volatile(
 | 
						|
                 // result.B-D += i.B x scale.A
 | 
						|
                 "  mul %B[i], %A[scale]                 \n\t"
 | 
						|
 | 
						|
                 "  add %B[result], r0                   \n\t"
 | 
						|
                 "  adc %C[result], r1                   \n\t"
 | 
						|
                 "  adc %D[result], %[zero]              \n\t"
 | 
						|
 | 
						|
                 // result.B-D += i.A x scale.B
 | 
						|
                 "  mul %A[i], %B[scale]                 \n\t"
 | 
						|
 | 
						|
                 "  add %B[result], r0                   \n\t"
 | 
						|
                 "  adc %C[result], r1                   \n\t"
 | 
						|
                 "  adc %D[result], %[zero]              \n\t"
 | 
						|
 | 
						|
                 // cleanup r1
 | 
						|
                 "  clr r1                               \n\t"
 | 
						|
 | 
						|
                 : [result] "+r" (result)
 | 
						|
                 : [i] "r" (i),
 | 
						|
                   [scale] "r" (scale),
 | 
						|
                   [zero] "r" (zero)
 | 
						|
                 : "r0", "r1"
 | 
						|
                 );
 | 
						|
 | 
						|
    result = result >> 16;
 | 
						|
    return result;
 | 
						|
#endif
 | 
						|
#else
 | 
						|
    #error "No implementation for scale16 available."
 | 
						|
#endif
 | 
						|
}
 | 
						|
///@}
 | 
						|
 | 
						|
///@defgroup Dimming Dimming and brightening functions
 | 
						|
///
 | 
						|
/// Dimming and brightening functions
 | 
						|
///
 | 
						|
/// The eye does not respond in a linear way to light.
 | 
						|
/// High speed PWM'd LEDs at 50% duty cycle appear far
 | 
						|
/// brighter then the 'half as bright' you might expect.
 | 
						|
///
 | 
						|
/// If you want your midpoint brightness leve (128) to
 | 
						|
/// appear half as bright as 'full' brightness (255), you
 | 
						|
/// have to apply a 'dimming function'.
 | 
						|
///@{
 | 
						|
 | 
						|
/// Adjust a scaling value for dimming
 | 
						|
LIB8STATIC uint8_t dim8_raw( uint8_t x)
 | 
						|
{
 | 
						|
    return scale8( x, x);
 | 
						|
}
 | 
						|
 | 
						|
/// Adjust a scaling value for dimming for video (value will never go below 1)
 | 
						|
LIB8STATIC uint8_t dim8_video( uint8_t x)
 | 
						|
{
 | 
						|
    return scale8_video( x, x);
 | 
						|
}
 | 
						|
 | 
						|
/// Linear version of the dimming function that halves for values < 128
 | 
						|
LIB8STATIC uint8_t dim8_lin( uint8_t x )
 | 
						|
{
 | 
						|
    if( x & 0x80 ) {
 | 
						|
        x = scale8( x, x);
 | 
						|
    } else {
 | 
						|
        x += 1;
 | 
						|
        x /= 2;
 | 
						|
    }
 | 
						|
    return x;
 | 
						|
}
 | 
						|
 | 
						|
/// inverse of the dimming function, brighten a value
 | 
						|
LIB8STATIC uint8_t brighten8_raw( uint8_t x)
 | 
						|
{
 | 
						|
    uint8_t ix = 255 - x;
 | 
						|
    return 255 - scale8( ix, ix);
 | 
						|
}
 | 
						|
 | 
						|
/// inverse of the dimming function, brighten a value
 | 
						|
LIB8STATIC uint8_t brighten8_video( uint8_t x)
 | 
						|
{
 | 
						|
    uint8_t ix = 255 - x;
 | 
						|
    return 255 - scale8_video( ix, ix);
 | 
						|
}
 | 
						|
 | 
						|
/// inverse of the dimming function, brighten a value
 | 
						|
LIB8STATIC uint8_t brighten8_lin( uint8_t x )
 | 
						|
{
 | 
						|
    uint8_t ix = 255 - x;
 | 
						|
    if( ix & 0x80 ) {
 | 
						|
        ix = scale8( ix, ix);
 | 
						|
    } else {
 | 
						|
        ix += 1;
 | 
						|
        ix /= 2;
 | 
						|
    }
 | 
						|
    return 255 - ix;
 | 
						|
}
 | 
						|
 | 
						|
///@}
 | 
						|
#endif
 |