Various header cleanups. NFC.

* Don't use a reserved identifier in include guards.
  * Use fabs() from <cmath> instead of our own ffabs().
    This shouldn't make any difference with modern toolchains.
  * Convert a few preprocessor macros to constexprs.

src/platform/gui.h

@@ -7,6 +7,8 @@
 #ifndef SOLVESPACE_GUI_H
 #define SOLVESPACE_GUI_H
 
+class RgbaColor;
+
 namespace Platform {
 
 //-----------------------------------------------------------------------------

src/resource.h

@@ -4,13 +4,14 @@
 // Copyright 2016 whitequark
 //-----------------------------------------------------------------------------
 
-#ifndef __RESOURCE_H
-#define __RESOURCE_H
+#ifndef SOLVESPACE_RESOURCE_H
+#define SOLVESPACE_RESOURCE_H
 
 class Camera;
 class Point2d;
 class Pixmap;
 class Vector;
+class RgbaColor;
 
 std::string LoadString(const std::string &name);
 std::string LoadStringFromGzip(const std::string &name);

src/solvespace.cpp

@@ -151,7 +151,7 @@ void SolveSpaceUI::Init() {
 }
 
 bool SolveSpaceUI::LoadAutosaveFor(const Platform::Path &filename) {
-    Platform::Path autosaveFile = filename.WithExtension(AUTOSAVE_EXT);
+    Platform::Path autosaveFile = filename.WithExtension(BACKUP_EXT);
 
     FILE *f = OpenFile(autosaveFile, "rb");
     if(!f)
@@ -474,7 +474,7 @@ bool SolveSpaceUI::GetFilenameAndSave(bool saveAs) {
 
     if(saveAs || saveFile.IsEmpty()) {
         Platform::FileDialogRef dialog = Platform::CreateSaveFileDialog(GW.window);
-        dialog->AddFilter(C_("file-type", "SolveSpace models"), { "slvs" });
+        dialog->AddFilter(C_("file-type", "SolveSpace models"), { SKETCH_EXT });
         dialog->ThawChoices(settings, "Sketch");
         if(!newSaveFile.IsEmpty()) {
             dialog->SetFilename(newSaveFile);
@@ -503,13 +503,13 @@ void SolveSpaceUI::Autosave()
     ScheduleAutosave();
 
     if(!saveFile.IsEmpty() && unsaved) {
-        SaveToFile(saveFile.WithExtension(AUTOSAVE_EXT));
+        SaveToFile(saveFile.WithExtension(BACKUP_EXT));
     }
 }
 
 void SolveSpaceUI::RemoveAutosave()
 {
-    Platform::Path autosaveFile = saveFile.WithExtension(AUTOSAVE_EXT);
+    Platform::Path autosaveFile = saveFile.WithExtension(BACKUP_EXT);
     RemoveFile(autosaveFile);
 }
 

src/solvespace.h

@@ -85,6 +85,7 @@ namespace SolveSpace {
 using std::min;
 using std::max;
 using std::swap;
+using std::fabs;
 
 #if defined(__GNUC__)
 __attribute__((noreturn))
@@ -116,44 +117,31 @@ inline double WRAP_SYMMETRIC(double v, double n) {
     return v;
 }
 
-// Why is this faster than the library function?
-inline double ffabs(double v) { return (v > 0) ? v : (-v); }
-
 #define CO(v) (v).x, (v).y, (v).z
 
-#define ANGLE_COS_EPS   (1e-6)
-#define LENGTH_EPS      (1e-6)
-#define VERY_POSITIVE   (1e10)
-#define VERY_NEGATIVE   (-1e10)
+static constexpr double ANGLE_COS_EPS =  1e-6;
+static constexpr double LENGTH_EPS    =  1e-6;
+static constexpr double VERY_POSITIVE =  1e10;
+static constexpr double VERY_NEGATIVE = -1e10;
 
 inline double Random(double vmax) {
     return (vmax*rand()) / RAND_MAX;
 }
 
+#include "platform/platform.h"
+#include "platform/gui.h"
+#include "resource.h"
+
 class Expr;
 class ExprVector;
 class ExprQuaternion;
 class RgbaColor;
 enum class Command : uint32_t;
 
-//================
-// From the platform-specific code.
-
-#include "platform/platform.h"
-#include "platform/gui.h"
-
-const size_t MAX_RECENT = 8;
-
-#define AUTOSAVE_EXT "slvs~"
-
+// Temporary heap, defined in the platform-specific code.
 void *AllocTemporary(size_t n);
 void FreeAllTemporary();
 
-// End of platform-specific functions
-//================
-
-#include "resource.h"
-
 enum class Unit : uint32_t {
     MM = 0,
     INCHES,
@@ -670,7 +658,9 @@ public:
     static void MenuFile(Command id);
     void Autosave();
     void RemoveAutosave();
-    static const size_t MAX_RECENT = 8;
+    static constexpr size_t MAX_RECENT = 8;
+    static constexpr const char *SKETCH_EXT = "slvs";
+    static constexpr const char *BACKUP_EXT = "slvs~";
     std::vector<Platform::Path> recentFiles;
     bool Load(const Platform::Path &filename);
     bool GetFilenameAndSave(bool saveAs);

src/system.cpp

@@ -187,15 +187,15 @@ bool System::SolveLinearSystem(double X[], double A[][MAX_UNKNOWNS],
         // greater. First, find a pivot (between rows i and N-1).
         max = 0;
         for(ip = i; ip < n; ip++) {
-            if(ffabs(A[ip][i]) > max) {
+            if(fabs(A[ip][i]) > max) {
                 imax = ip;
-                max = ffabs(A[ip][i]);
+                max = fabs(A[ip][i]);
             }
         }
         // Don't give up on a singular matrix unless it's really bad; the
         // assumption code is responsible for identifying that condition,
         // so we're not responsible for reporting that error.
-        if(ffabs(max) < 1e-20) continue;
+        if(fabs(max) < 1e-20) continue;
 
         // Swap row imax with row i
         for(jp = 0; jp < n; jp++) {
@@ -217,7 +217,7 @@ bool System::SolveLinearSystem(double X[], double A[][MAX_UNKNOWNS],
     // We've put the matrix in upper triangular form, so at this point we
     // can solve by back-substitution.
     for(i = n - 1; i >= 0; i--) {
-        if(ffabs(A[i][i]) < 1e-20) continue;
+        if(fabs(A[i][i]) < 1e-20) continue;
 
         temp = B[i];
         for(j = n - 1; j > i; j--) {
@@ -309,7 +309,7 @@ bool System::NewtonSolve(int tag) {
             if(isnan(mat.B.num[i])) {
                 return false;
             }
-            if(ffabs(mat.B.num[i]) > CONVERGE_TOLERANCE) {
+            if(fabs(mat.B.num[i]) > CONVERGE_TOLERANCE) {
                 converged = false;
                 break;
             }
@@ -493,7 +493,7 @@ didnt_converge:
     SK.constraint.ClearTags();
     // Not using range-for here because index is used in additional ways
     for(i = 0; i < eq.n; i++) {
-        if(ffabs(mat.B.num[i]) > CONVERGE_TOLERANCE || isnan(mat.B.num[i])) {
+        if(fabs(mat.B.num[i]) > CONVERGE_TOLERANCE || isnan(mat.B.num[i])) {
             // This constraint is unsatisfied.
             if(!mat.eq[i].isFromConstraint()) continue;