Optimize character rendering

[GOROman]

Summary

• improve printing speed by removing temporary String objects

Testing

• git status --short

[Copilot]

Pull Request Overview

This PR optimizes character rendering by eliminating per-iteration String allocations and using direct char access for display.

• Introduce a const char* pointer to buffer data and extract each character directly
• Replace String.substring and canvas.printf calls with canvas.write(ch)
• Remove temporary String objects in the print loop

Comments suppressed due to low confidence (3)

src/main.cpp:204

• Consider using buffer.length() (or buffer.size()) instead of the external len variable to ensure you iterate over the actual string length and avoid potential out-of-bounds access.

for (int i = 0; i < len; i++)

src/main.cpp:202

• [nitpick] The variable name cstr is ambiguous; consider renaming it to something more descriptive, like bufferChars or dataPtr, to clarify its purpose.

const char *cstr = buffer.c_str();

src/main.cpp:201

• [nitpick] The variable count could be renamed to printedCount or similar to better convey that it tracks the number of characters printed.

int count = 0;

[Copilot]

[nitpick] Consider adding a comment to explain why spaces and question marks are skipped here, improving code readability for future maintainers.

Suggested change

	// Skip spaces and question marks to avoid unnecessary sound effects or visual updates.

[Copilot]

Pull Request Overview

This PR optimizes the task_print function by replacing per-character String allocations with direct buffer access and a single-character write call to improve rendering speed.

• Introduces a const char* pointer to the string data
• Replaces String.substring with indexing into the C-string
• Switches from canvas.printf to canvas.write for single-character output

Comments suppressed due to low confidence (3)

src/main.cpp:202

• [nitpick] The variable name cstr is generic; consider renaming to buffer_cstr or textPtr to improve readability and clarify its relationship to buffer.

const char *cstr = buffer.c_str();

src/main.cpp:206

• Indexing into a C-string may split multi-byte/UTF-8 characters, leading to rendering errors. Consider using a method that respects character boundaries (e.g., substring(i, i + 1)) or iterate with a Unicode-aware iterator.

char ch = cstr[i];

src/main.cpp:202

• The loop uses len but it isn’t shown as being set to buffer.length(). Ensure len is defined as size_t len = buffer.length(); after creating buffer to avoid out-of-bounds access.

const char *cstr = buffer.c_str();