bill/whetstone_DSL
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Step 78: line numbers and gutter

Browse Source
This commit is contained in:
Bill
2026-02-09 09:06:07 -07:00
parent 65b714547f
commit b18e41c6d0
4 changed files with 171 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files

90
editor/src/CodeEditorWidget.h
View File

@@ -20,6 +20,9 @@ struct CodeEditorOptions {
struct CodeEditorResult {
bool changed = false;
int cursorByte = 0;
int lineCount = 0;
float gutterWidth = 0.0f;
int currentLine = 0;
};
class CodeEditorWidget {
@@ -58,6 +61,7 @@ public:
// Measure
const float lineHeight = ImGui::GetTextLineHeightWithSpacing();
const float charAdvance = font->CalcTextSizeA(font->FontSize, FLT_MAX, -1.0f, "M").x;
const float gutterWidth = calcGutterWidth(lineCount, font, charAdvance);
// Estimate content size for scrollbars
int maxLineLen = 0;
@@ -67,7 +71,8 @@ public:
int len = std::max(0, end - start);
maxLineLen = std::max(maxLineLen, len);
}
ImVec2 contentSize(maxLineLen * charAdvance + 4.0f, lineCount * lineHeight + 4.0f);
ImVec2 contentSize(gutterWidth + maxLineLen * charAdvance + 4.0f,
lineCount * lineHeight + 4.0f);
ImGui::BeginChild(id, size, false, ImGuiWindowFlags_HorizontalScrollbar);
ImVec2 origin = ImGui::GetCursorScreenPos();
@@ -78,7 +83,8 @@ public:
ImDrawList* drawList = ImGui::GetWindowDrawList();
const float scrollX = ImGui::GetScrollX();
const float scrollY = ImGui::GetScrollY();
ImVec2 base(origin.x - scrollX, origin.y - scrollY);
ImVec2 gutterBase(origin.x, origin.y - scrollY);
ImVec2 textBase(origin.x + gutterWidth - scrollX, origin.y - scrollY);
// Focus and input
const bool hovered = ImGui::IsWindowHovered();
@@ -87,14 +93,27 @@ public:
// Mouse handling
if (hovered && ImGui::IsMouseClicked(ImGuiMouseButton_Left)) {
ImGui::SetKeyboardFocusHere(-1);
cursor_ = positionFromMouse(ImGui::GetMousePos(), base, lineStarts, text, charAdvance, lineHeight);
selStart_ = cursor_;
selEnd_ = cursor_;
const ImVec2 mouse = ImGui::GetMousePos();
if (mouse.x < origin.x + gutterWidth) {
int line = lineFromMouseY(mouse.y, gutterBase.y, lineHeight, lineCount);
int lineStart = lineStarts[line];
int lineEnd = (line + 1 < lineCount) ? lineStarts[line + 1] : (int)text.size();
cursor_ = lineStart;
selStart_ = lineStart;
selEnd_ = lineEnd;
} else {
cursor_ = positionFromMouse(mouse, textBase, lineStarts, text, charAdvance, lineHeight);
selStart_ = cursor_;
selEnd_ = cursor_;
}
selecting_ = true;
}
if (hovered && selecting_ && ImGui::IsMouseDown(ImGuiMouseButton_Left)) {
int pos = positionFromMouse(ImGui::GetMousePos(), base, lineStarts, text, charAdvance, lineHeight);
selEnd_ = pos;
const ImVec2 mouse = ImGui::GetMousePos();
if (mouse.x >= origin.x + gutterWidth) {
int pos = positionFromMouse(mouse, textBase, lineStarts, text, charAdvance, lineHeight);
selEnd_ = pos;
}
}
if (selecting_ && ImGui::IsMouseReleased(ImGuiMouseButton_Left)) {
selecting_ = false;
@@ -110,12 +129,35 @@ public:
const int visibleLines = (int)(ImGui::GetContentRegionAvail().y / lineHeight) + 2;
const int lastLine = std::min(lineCount - 1, firstLine + visibleLines);
const float textAreaWidth = std::max(0.0f,
(ImGui::GetWindowContentRegionMax().x - ImGui::GetWindowContentRegionMin().x) - gutterWidth);
const int currentLine = lineFromPos(cursor_, lineStarts);
for (int ln = firstLine; ln <= lastLine; ++ln) {
int start = lineStarts[ln];
int end = (ln + 1 < lineCount) ? lineStarts[ln + 1] - 1 : (int)text.size();
int len = std::max(0, end - start);
float y = base.y + ln * lineHeight;
float y = textBase.y + ln * lineHeight;
// Gutter background
ImVec2 gutterA(origin.x, y);
ImVec2 gutterB(origin.x + gutterWidth, y + lineHeight);
drawList->AddRectFilled(gutterA, gutterB, IM_COL32(20, 20, 20, 255));
// Line number (right-aligned)
char numBuf[16];
snprintf(numBuf, sizeof(numBuf), "%d", ln + 1);
ImVec2 numSize = font->CalcTextSizeA(font->FontSize, FLT_MAX, -1.0f, numBuf);
ImVec2 numPos(origin.x + gutterWidth - 4.0f - numSize.x, y);
drawList->AddText(font, font->FontSize, numPos, IM_COL32(120, 120, 120, 255), numBuf);
// Current line highlight (text area only)
if (ln == currentLine) {
ImVec2 hlA(textBase.x, y);
ImVec2 hlB(textBase.x + textAreaWidth, y + lineHeight);
drawList->AddRectFilled(hlA, hlB, IM_COL32(40, 40, 40, 120));
}
// Selection background
if (hasSelection()) {
@@ -126,8 +168,8 @@ public:
if (lineSelStart < lineSelEnd) {
int colA = lineSelStart - start;
int colB = lineSelEnd - start;
ImVec2 a(base.x + colA * charAdvance, y);
ImVec2 b(base.x + colB * charAdvance, y + lineHeight);
ImVec2 a(textBase.x + colA * charAdvance, y);
ImVec2 b(textBase.x + colB * charAdvance, y + lineHeight);
drawList->AddRectFilled(a, b, IM_COL32(60, 100, 160, 120));
}
}
@@ -156,7 +198,7 @@ public:
chunk.pop_back();
}
ImVec2 p(base.x + (pos - start) * charAdvance, y);
ImVec2 p(textBase.x + (pos - start) * charAdvance, y);
drawList->AddText(font, font->FontSize, p, colorFor(cat), chunk.c_str());
pos = spanEnd;
@@ -168,11 +210,11 @@ public:
const double t = ImGui::GetTime();
const bool blinkOn = ((int)(t * 2.0)) % 2 == 0;
if (blinkOn) {
int curLine = lineFromPos(cursor_, lineStarts);
int curLine = currentLine;
int lineStart = lineStarts[curLine];
int col = cursor_ - lineStart;
float x = base.x + col * charAdvance;
float y = base.y + curLine * lineHeight;
float x = textBase.x + col * charAdvance;
float y = textBase.y + curLine * lineHeight;
drawList->AddLine(ImVec2(x, y), ImVec2(x, y + lineHeight), IM_COL32(240, 240, 240, 255), 1.0f);
}
}
@@ -180,6 +222,9 @@ public:
ImGui::EndChild();
result.cursorByte = cursor_;
result.lineCount = lineCount;
result.gutterWidth = gutterWidth;
result.currentLine = currentLine;
return result;
}
@@ -223,6 +268,12 @@ private:
return line;
}
static int lineFromMouseY(float mouseY, float baseY, float lineHeight, int lineCount) {
int line = (int)((mouseY - baseY) / lineHeight);
line = std::max(0, std::min(line, lineCount - 1));
return line;
}
static int positionFromMouse(const ImVec2& mouse,
const ImVec2& base,
const std::vector<int>& lineStarts,
@@ -241,6 +292,17 @@ private:
return start + col;
}
static float calcGutterWidth(int lineCount, ImFont* font, float charAdvance) {
int digits = 1;
int n = std::max(1, lineCount);
while (n >= 10) { n /= 10; ++digits; }
const float pad = 6.0f;
float digitsWidth = font->CalcTextSizeA(font->FontSize, FLT_MAX, -1.0f,
std::string(digits, '0').c_str()).x;
float width = digitsWidth + pad * 2.0f;
return std::max(width, charAdvance * 2.0f + pad * 2.0f);
}
void deleteSelection(std::string& text, bool& changed) {
if (!hasSelection()) return;
int a = std::min(selStart_, selEnd_);