gear step ratio

Hello everyone
help to understand the code
need to increase
pulse_buffer in 1.2
but the code only allows integer 1 2 and so on.
tried changing the pulse_buffer datatype to round off STEPS_PR_ENCODER_PULSE

but it only works equally well with the whole. can still some parameter increase to then divide?

#define ENCODER_PULSE_PIN 2
#define ENCODER_DIR_PIN   3
#define DRIVER_STEP_PIN   4
#define DRIVER_DIR_PIN    7
#define DRIVER_EN_PIN     8

#define STEPS_PR_ENCODER_PULSE  1
#define DRIVER_PULSE_PERIOD_US  1

enum Driver_pulse_state_enum {PULSE_IDLE, PULSE_HIGH, PULSE_LOW};



uint8_t dir = LOW;
uint16_t pulse_buffer = 0;
unsigned long time_now = 0;
uint16_t driver_pulse_hold_time_us = DRIVER_PULSE_PERIOD_US/2;
uint8_t driver_pulse_state = PULSE_IDLE;





void setup() {

  pinMode(ENCODER_PULSE_PIN, INPUT);
  pinMode(ENCODER_DIR_PIN, INPUT);
  pinMode(DRIVER_STEP_PIN, OUTPUT);
  pinMode(DRIVER_DIR_PIN, OUTPUT);
  pinMode(DRIVER_EN_PIN, OUTPUT);
   
  attachInterrupt(digitalPinToInterrupt(ENCODER_PULSE_PIN), encoderISR, RISING);

  digitalWrite(DRIVER_EN_PIN, HIGH);





void loop() {


  if((pulse_buffer) && (driver_pulse_state == PULSE_IDLE)){
    driver_pulse_state = PULSE_HIGH;
    digitalWrite(DRIVER_DIR_PIN, digitalRead(ENCODER_DIR_PIN));
    digitalWrite(DRIVER_STEP_PIN, HIGH);
    time_now = micros();
  }

  if((micros() - time_now > driver_pulse_hold_time_us) && (driver_pulse_state == PULSE_LOW)){
    driver_pulse_state = PULSE_HIGH;
    digitalWrite(DRIVER_STEP_PIN, HIGH);
    time_now = micros();
  }

  if((micros() - time_now > driver_pulse_hold_time_us) && (driver_pulse_state == PULSE_HIGH)){
    digitalWrite(DRIVER_STEP_PIN, LOW);
    time_now = micros();
     
    pulse_buffer -= 1;
    if(pulse_buffer < 0){
      pulse_buffer = 0;
    }
     
    if(pulse_buffer){
      driver_pulse_state = PULSE_LOW;
    }
    else{
      driver_pulse_state = PULSE_IDLE;
    }
  }


  
}

void encoderISR(){
  pulse_buffer += STEPS_PR_ENCODER_PULSE;
}