create_new_font.py

# used for preparing fonts
# input is the file path to the .c file received from https://littlevgl.com/ttf-font-to-c-array

import fileinput
import sys
import re
import os

fontSourceFileName = "font_source.py"
destFolder = "src"


def createSourceFontFile() -> int:
        foundOpen = False  # indicate if the beginning of c source array is found
        foundFirstChar = False  # whether first character in the c header file is found
        newestFoundWidth = 0  # width of the most recent character, used for building the dict
        firstCharFound = 0  # ascii of the name of first char found(ie 97 for a)

        widthPattern = re.compile(".*Width: ([0-9]*) \*/")  # find character width in c comment
        charNamePattern = re.compile(".*Unicode: U\+([0-9]*).*\*/")  # find character name in a c comment

        # create scratch file to store bit map
        try:
                processedFontFile = open(fontSourceFileName, 'w')
        except:
            print("Can't create new files")
            sys.exit(0)  # quit Python

        for line in fileinput.input():
                if(foundOpen):
                        searchResult = re.search("\s*};\s*", line)
                        if(searchResult != None):
                                processedFontFile.write("]}]")
                                processedFontFile.close()
                                break

                        tempLine = line
                        tempLine = re.sub("{", "", tempLine)
                        tempLine = re.sub("\w*//.*", "", tempLine)  # delete all c comments

                        widthResult = widthPattern.match(line)
                        if(widthResult != None):
                                newestFoundWidth = int(widthResult.group(1))

                        if(foundFirstChar):
                                # start creating opening of python dict
                                tempLine = re.sub("/\*", "]}#", tempLine)
                                tempLine = re.sub("\*/", "\n,{ \"length\": " + str(newestFoundWidth) + ", \n\"bitmap\": [", tempLine)
                        else:
                                searchResult = re.search("/\*", line)
                                if(searchResult != None):
                                        firstCharSearchRes = charNamePattern.match(line)
                                        if(firstCharSearchRes != None):
                                                firstCharFound = int(firstCharSearchRes.group(1), 16)

                                        tempLine = re.sub("/\*", "#", tempLine)
                                        tempLine = re.sub("\*/", "\n{ \"length\": " + str(newestFoundWidth) + ", \n\"bitmap\": [", tempLine)
                                        foundFirstChar = True

                        processedFontFile.write(tempLine)

                # check for beginning of c array
                if(False == foundOpen):
                        searchResult = re.search("\s*static const uint8_t source_code_pro_oled_glyph_bitmap\[\] =\s*", line)
                        if(searchResult != None):
                                foundOpen = True
                                processedFontFile.write("bitmapData = [")
        return firstCharFound


def makeCFile(firstCharFound: int):
        import numpy as np
        import font_source as ft

        BITS_PER_COLUMN = 8
        TOTAL_PAGE = 2
        MIN_REMOVAL_LEN = 5  # must be at least this long to have empty line removed

        tempMatrix = []
        finalList = []
        for currChar, bitDict in enumerate(ft.bitmapData):
                # build a matrix representation of the character
                for index in range(0, len(bitDict["bitmap"])):
                        tempMatrix.append([])
                        # print(hex(bitDict["bitmap"][index]))
                        for bitOrder in range(7, -1, -1):
                                # print(1 << bitOrder)
                                if (bitDict["bitmap"][index] & (1 << bitOrder)) > 0:
                                        tempMatrix[index].append(1)
                                else:
                                        tempMatrix[index].append(0)
                # print(tempMatrix)
                m = np.array(tempMatrix)
                m = np.transpose(m)
                # print(np.array(tempMatrix))
                print("Before removal: ")
                print(m)
                m = m.tolist()
                lineToRemove = []

                # remove blank line to make character look consistent
                if(bitDict["length"] >= MIN_REMOVAL_LEN):
                        for currPosition, vertLine in enumerate(m):
                                print(currPosition)

                                if (all(bit == 0 for bit in vertLine)):
                                        lineToRemove.append(currPosition)
                        lineToRemove.sort(reverse= True)
                        for index in lineToRemove:
                                del m[index]

                print("After removal: ")
                print(m)

                finalList.append([])

                for currPosition, i in enumerate(m):
                        tempSum = 0
                        tempCounter = 0
                        # package the number
                        for j in i:
                                tempSum = tempSum + (j << tempCounter)
                                tempCounter += 1
                        appendCounter = 0
                        # spread the number into 8 bit packs
                        while(tempSum > 0):
                                finalList[currChar].append(tempSum & 0xff)
                                tempSum >>= BITS_PER_COLUMN
                                appendCounter += 1

                        # pad unoccupied page
                        for k in range(0, TOTAL_PAGE - appendCounter):
                                finalList[currChar].append(0)

                tempMatrix = []

        # create c header file
        try:
                currDir = os.path.dirname(os.path.abspath(__file__))
                # print(currDir)
                relDir = destFolder + "/" + "oled_font_" + sys.argv[2] + ".h"
                finalPath = os.path.join(currDir, relDir)
                # print(finalPath)
                cHeaderFile = open(finalPath, 'w')

        except:
                print("Can't create new files\n")
                sys.exit(0)

        cHeaderFile.write("#ifndef _OLED_FONT_H_" + (sys.argv[2]).upper() + "\n")
        cHeaderFile.write("#define _OLED_FONT_H_" + (sys.argv[2]).upper() + "\n")
        cHeaderFile.write("" + "\n")
        cHeaderFile.write("#ifdef __cplusplus" + "\n")
        cHeaderFile.write("extern \"C\" {" + "\n")
        cHeaderFile.write("#endif" + "\n")
        cHeaderFile.write("#include <stdint.h>" + "\n")
        cHeaderFile.write('#include "oled_font.h"' + "\n")
        cHeaderFile.write("" + "\n")
        cHeaderFile.write("extern const fontSetDesc " + sys.argv[2] + "_set;" + "\n")
        cHeaderFile.write("" + "\n")
        cHeaderFile.write("#ifdef __cplusplus" + "\n")
        cHeaderFile.write("}" + "\n")
        cHeaderFile.write("#endif" + "\n")
        cHeaderFile.write("#endif" + "\n")

        try:
                cHeaderFile.close()
        except:
                print("Can't close c header file")
                sys.exit(0)

        try:
                currDir = os.path.dirname(os.path.abspath(__file__))
                # print(currDir)
                relDir = destFolder + "/" + "oled_font_" + sys.argv[2] + ".c"
                finalPath = os.path.join(currDir, relDir)
                # print(finalPath)
                cSourceFile = open(finalPath, 'w')

        except:
                print("Can't create new files\n")
                sys.exit(0)

        # start writing to the c source file
        cSourceFile.write('#include "oled_font_' + sys.argv[2] + '.h"\n')
        cSourceFile.write("#include <stdint.h>\n")
        cSourceFile.write("\n")
        cSourceFile.write("#define TOTAL_CHAR " + str(len(finalList)) + "\n")
        cSourceFile.write("#define CHAR_LIST_OFFSET " + str(firstCharFound) + "\n\n")

        cSourceFile.write("const fontDescList " + sys.argv[2] + "[TOTAL_CHAR] = {\n")
        structMember = ""
        for charMoved in finalList:
                structMember = structMember.join(["{.glyphLen = ", str(len(charMoved)), ", .glyphBitmap=(uint8_t[]){", ', '.join(map(str, charMoved)), "}}, /* " + chr(firstCharFound) + " */ \n"])
                cSourceFile.write(structMember)
                structMember = ""
                firstCharFound += 1

        cSourceFile.write("\n};\n\n")

        # write font set definition
        cSourceFile.write("const fontSetDesc " + sys.argv[2] + "_set = {\n")
        cSourceFile.write("\t.totalChar = TOTAL_CHAR,\n")
        cSourceFile.write("\t.charOffset = CHAR_LIST_OFFSET,\n")
        cSourceFile.write("\t.descList = " + sys.argv[2] + ", \n};\n")

        try:
                cSourceFile.close()
        except:
                print("Can't close c source file")
                sys.exit(0)


def main():
        makeCFile(createSourceFontFile())
        os.remove(fontSourceFileName)


if __name__ == '__main__':
	main()