将操纵杆轴值转换为十六进制三元组代码答案

【问题标题】：Converting joystick axis values to hex triplet codes将操纵杆轴值转换为十六进制三元组代码
【发布时间】：2018-09-10 00:30:01
【问题描述】：

在 pygame 中使用 PS4 控制器，我已经想出了如何捕获可以变化为 -1 或 1 的轴旋转，但我不知道如何将这些数字转换为色环喜欢比例，以便将其转换为十六进制三元组数字。
模仿色环的值比任何东西都重要，因为我不希望操纵杆在不运动时捕捉颜色。 Picture
（因为这有点令人困惑，所以基本上我希望能够移动我的操纵杆并根据它移动的位置捕获一个准确的十六进制三元组数字）

这是我目前的代码：

import pygame

# Define some colors
BLACK    = (   0,   0,   0)
WHITE    = ( 62, 210, 255)

# This is a simple class that will help us print to the screen
# It has nothing to do with the joysticks, just outputting the
# information.
class TextPrint:
    def __init__(self):
        self.reset()
        self.font = pygame.font.Font(None, 25)

    def print(self, screen, textString):
        textBitmap = self.font.render(textString, True, BLACK)
        screen.blit(textBitmap, [self.x, self.y])
        self.y += self.line_height

    def reset(self):
        self.x = 25
        self.y = 25
        self.line_height = 30

    def indent(self):
        self.x += 10

    def unindent(self):
        self.x -= 10


pygame.init()

# Set the width and height of the screen [width,height]
size = [900, 1080]
screen = pygame.display.set_mode(size)

pygame.display.set_caption("PS4Testing")

#Loop until the user clicks the close button.
done = False

# Used to manage how fast the screen updates
clock = pygame.time.Clock()

# Initialize the joysticks
pygame.joystick.init()

# Get ready to print
textPrint = TextPrint()

# -------- Main Program Loop -----------
while done==False:
    # EVENT PROCESSING STEP
    for event in pygame.event.get(): # User did something
        if event.type == pygame.QUIT: # If user clicked close
            done=True # Flag that we are done so we exit this loop




    screen.fill(WHITE)
    textPrint.reset()

    # Get count of joysticks
    joystick_count = pygame.joystick.get_count()


    # For each joystick:
    for i in range(joystick_count):
        joystick = pygame.joystick.Joystick(i)
        joystick.init()

        # Usually axis run in pairs, up/down for one, and left/right for
        # the other.
        axes = joystick.get_numaxes()


        for i in range( axes ):
            axis = joystick.get_axis( i )
            textPrint.print(screen, "Axis {} value: {:>6.3f}".format(i, axis) )
        textPrint.unindent()



    # ALL CODE TO DRAW SHOULD GO ABOVE THIS COMMENT

    # Go ahead and update the screen with what we've drawn.
    pygame.display.flip()

    # Limit to 20 frames per second
    clock.tick(20)

# Close the window and quit.
# If you forget this line, the program will 'hang'
# on exit if running from IDLE.
pygame.quit ()

来自official pygame documentation的修改代码
任何帮助将不胜感激

【问题讨论】：

我不知道 pygame 返回什么，但从你的输出看，它看起来像是三个浮点数。在将这些整数转换为十六进制数字对之前，您需要弄清楚如何将它们映射到 0-255 范围内的整数。例如，如果它们是从 0.0 到 1.0 的浮点数，您可能需要round(x*255)。然后只需使用格式字符串02x 而不是>6.3f，并将生成的三个字符串连接在一起而不是仅仅打印它们。米

标签： python colors pygame joystick

【解决方案1】：

我的计划：

找出摇杆上摇杆的角度
使用 HSV 和摇杆角度获取 RGB 值
转换为十六进制

寻找摇杆的角度

首先，我们需要找到操纵杆的角度。我们可以使用law of cosines 和axis 语句作为三角形边的长度来做到这一点（因为它们来自一个点/中心）。

在此块中存储轴语句：

for i in range( axes ):
        axis = joystick.get_axis( i )
        #Storing axis statement
        if i == 0:
            Xaxis = axis
        elif i == 1:
            Yaxis = axis

        textPrint.print(screen, "Axis {} value: {:>6.3f}".format(i, axis) )

我们存储它们是因为在 for 循环中我们一次只能使用一条语句。

然后定义一个返回摇杆角度的函数。我们需要为pi 和acos 使用math 模块。

def get_angle(Xaxis,Yaxis):
    #To avoid ZeroDivisionError
    #P.S. - you can improve it a bit.
    if Xaxis == 0:
        Xaxis = 0.001
    if Yaxis == 0:
        Yaxis = 0.001
    #defining the third side of a triangle using the Pythagorean theorem
    b = ((Xaxis)**2 + (Yaxis)**2)**0.5
    c = Xaxis
    a = Yaxis
    #Using law of cosines we'll find angle using arccos of cos
    #math.acos returns angles in radians, so we need to multiply it by 180/math.pi
    angle =  math.acos((b**2 + c**2 - a**2) / (2*b*c)) * 180/math.pi
    #It'll fix angles to be in range of 0 to 360
    if Yaxis > 0:
        angle = 360 - angle
    return angle

现在get_angle(Xaxis,Yaxis) 将返回摇杆的角度。东0°，北90°，西180°，南270°。

获取 HSV 并转换为 RGB

我们有棒的角度，我们可以用它来制作 HSV 颜色，然后将其转换为 RGB，因为色轮是基于颜色的色调。

色相与棒的角度范围相同，因此我们可以使用棒的角度作为色调。

使用Wikipedia 中的公式，定义一个将 HSV 转换为 RGB 的函数。

def hsv_to_rgb(H,S,V):
    #0 <= H <= 360
    #0 <= S <= 1
    #0 <= V <= 1
    C = V * S
    h = H/60
    X = C * (1 - abs(h % 2 -1))

    #Yes, Python can compare like "0 <= 2 > 1"
    if 0 <= h <= 1:
        r = C; g = X; b = 0
    elif 1 <= h <= 2:
        r = X; g = C; b = 0
    elif 2 <= h <= 3:
        r = 0; g = C; b = X
    elif 3 <= h <= 4:
        r = 0; g = X; b = C
    elif 4 <= h <= 5:
        r = X; g = 0; b = C
    elif 5 <= h < 6:
        r = C; g = 0; b = X

    m = V - C

    #Final computing and converting from 0 - 1 to 0 - 255 
    R = int((r+m)*255)
    G = int((g+m)*255)
    B = int((b+m)*255)

    return [R,G,B]

现在hsv_to_rgb(get_angle(Xaxis,Yaxis),1,1) 将返回 0 - 255 范围内的红色、绿色和蓝色列表（以便于十六进制转换）。在这种情况下，饱和度和值不是必需的。

转换为十六进制

最简单的部分。我们需要获取 RGB 列表并将值转换为十六进制。

colors = hsv_to_rgb(get_angle(Xaxis,Yaxis),1,1)
#Converting to hex
lst = list(map(hex,colors))
#Cutting the "0x" part
for i in range(len(lst)):
    lst[i] = lst[i][2:]
    #If one of the colors has only one digit, extra 0 will be added for a better look
    if len(lst[i]) == 1:
        lst[i] = "0"+str(lst[i])
print(get_angle(Xaxis,Yaxis))

将打印#ff0000、#00ff00 和#0000ff 之类的内容。

您也可以让您的程序实时显示颜色变化，只需在此块中添加WHITE = colors。 如果您患有光敏性癫痫，请勿使用它。

合并所有内容

将两个函数从第一个点和第二个点放在开头的某个位置。

将第一个点的存储添加到块中

for i in range( axes ):
    axis = joystick.get_axis( i )
    textPrint.print(screen, "Axis {} value: {:>6.3f}".format(i, axis) )

从块之后的第三点添加转换。我建议制作一个死亡区域功能。

death_zone = 0.1
if abs(Xaxis) > death_zone or abs(Yaxis) > death_zone:
    #If you prefer HSV color wheel, use hsv_to_rgb(get_angle(Xaxis,Yaxis),1,1)
    #Else if you prefer RGB color wheel, use hsv_to_rgb(360-get_angle(Xaxis,Yaxis),1,1)
    colors = hsv_to_rgb(get_angle(Xaxis,Yaxis),1,1)
    #Converting to hex
    lst = list(map(hex,colors))
    #Cutting the "0x" part
    for i in range(len(lst)):
        lst[i] = lst[i][2:]
        #If one of the colors has only one digit, extra 0 will be added for a better look
        if len(lst[i]) == 1:
            lst[i] = "0"+str(lst[i])
    print("#"+"".join(lst))

这就是你的代码的样子：

附： - 您可能需要更改一些代码，因为我认为我的操纵杆的轴没有正确捕获。

import pygame
import math

# Define some colors
BLACK    = (   0,   0,   0)
WHITE    = ( 62, 210, 255)

def hsv_to_rgb(H,S,V):
    #Accirding to https://en.wikipedia.org/wiki/HSL_and_HSV#From_HSV
    #0 <= H <= 360
    #0 <= S <= 1
    #0 <= V <= 1
    C = V * S
    h = H/60
    X = C * (1 - abs(h % 2 -1))

    #Yes, Python can compare like "0 <= 2 > 1"
    if 0 <= h <= 1:
        r = C; g = X; b = 0
    elif 1 <= h <= 2:
        r = X; g = C; b = 0
    elif 2 <= h <= 3:
        r = 0; g = C; b = X
    elif 3 <= h <= 4:
        r = 0; g = X; b = C
    elif 4 <= h <= 5:
        r = X; g = 0; b = C
    elif 5 <= h < 6:
        r = C; g = 0; b = X

    m = V - C

    #Final computing and converting from 0 - 1 to 0 - 255 
    R = int((r+m)*255)
    G = int((g+m)*255)
    B = int((b+m)*255)

    return [R,G,B]

def get_angle(Xaxis,Yaxis):
    #To avoid ZeroDivisionError
    #P.S. - you can improve it a bit.
    if Xaxis == 0:
        Xaxis = 0.001
    if Yaxis == 0:
        Yaxis = 0.001
    #defining the third side of a triangle using the Pythagorean theorem
    b = ((Xaxis)**2 + (Yaxis)**2)**0.5
    c = Xaxis
    a = Yaxis
    #Using law of cosines we'll fing angle using arccos of cos
    #math.acos returns angles in radians, so we need to multiply it by 180/math.pi
    angle =  math.acos((b**2 + c**2 - a**2) / (2*b*c)) * 180/math.pi
    #It'll fix angles to be in range of 0 to 360
    if Yaxis > 0:
        angle = 360 - angle
    return angle

# This is a simple class that will help us print to the screen
# It has nothing to do with the joysticks, just outputting the
# information.
class TextPrint:
    def __init__(self):
        self.reset()
        self.font = pygame.font.Font(None, 25)

    def print(self, screen, textString):
        textBitmap = self.font.render(textString, True, BLACK)
        screen.blit(textBitmap, [self.x, self.y])
        self.y += self.line_height

    def reset(self):
        self.x = 25
        self.y = 25
        self.line_height = 30

    def indent(self):
        self.x += 10

    def unindent(self):
        self.x -= 10


pygame.init()

# Set the width and height of the screen [width,height]
size = [900, 1080]
screen = pygame.display.set_mode(size)

pygame.display.set_caption("PS4Testing")

#Loop until the user clicks the close button.
done = False

# Used to manage how fast the screen updates
clock = pygame.time.Clock()

# Initialize the joysticks
pygame.joystick.init()

# Get ready to print
textPrint = TextPrint()

# -------- Main Program Loop -----------
while done==False:
    # EVENT PROCESSING STEP
    for event in pygame.event.get(): # User did something
        if event.type == pygame.QUIT: # If user clicked close
            done=True # Flag that we are done so we exit this loop




    screen.fill(WHITE)
    textPrint.reset()

    # Get count of joysticks
    joystick_count = pygame.joystick.get_count()


    # For each joystick:
    for i in range(joystick_count):
        joystick = pygame.joystick.Joystick(i)
        joystick.init()

        # Usually axis run in pairs, up/down for one, and left/right for
        # the other.
        axes = joystick.get_numaxes()


        for i in range( axes ):
            axis = joystick.get_axis( i )
            #Storing axis statement
            if i == 0:
                Xaxis = axis
            elif i == 1:
                Yaxis = axis

            textPrint.print(screen, "Axis {} value: {:>6.3f}".format(i, axis) )
        textPrint.unindent()

        #If joystick is not in the center
        #Death zone is used to not capture joystick if it's very close to the center
        death_zone = 0.1
        if abs(Xaxis) > death_zone or abs(Yaxis) > death_zone:
            #If you prefer HSV color wheel, use hsv_to_rgb(get_angle(Xaxis,Yaxis),1,1)
            #Else if you prefer RGB color wheel, use hsv_to_rgb(360-get_angle(Xaxis,Yaxis),1,1)
            colors = hsv_to_rgb(get_angle(Xaxis,Yaxis),1,1)
            #Converting to hex
            lst = list(map(hex,colors))
            #Cutting the "0x" part
            for i in range(len(lst)):
                lst[i] = lst[i][2:]
                #If one of the colors has only one digit, extra 0 will be added for a better look
                if len(lst[i]) == 1:
                    lst[i] = "0"+str(lst[i])
            print("#"+"".join(lst))
            #You can use it to see color change in real time.
            #But I don't recomend to use it if you have photosensitive epilepsy.
            #WHITE = colors

    # ALL CODE TO DRAW SHOULD GO ABOVE THIS COMMENT

    # Go ahead and update the screen with what we've drawn.
    pygame.display.flip()

    # Limit to 20 frames per second
    clock.tick(20)

# Close the window and quit.
# If you forget this line, the program will 'hang'
# on exit if running from IDLE.
pygame.quit ()

【讨论】：