Merge pull request #11 from inkyblackness/float-sliders

Float sliders thanks to @Hperigo

CONTRIBUTING.md

@@ -20,3 +20,28 @@ At the moment, this library is primarily used by **InkyBlackness**. If you can a
 * Code is properly formatted & linted (use [golangci-lint](https://github.com/golangci/golangci-lint) for a full check)
 * Public Go API is documented (copied documentation from **Dear ImGui** is acceptable and recommended, assuming it is adapted regarding type names)
 * API and version philosophies are respected (see README.md)
+
+#### Clarification on API naming and signatures
+
+If an **Dear ImGui** function has the signature of
+
+```
+SomeControl(const char *label, int value, int optArg1 = 0, const char *optArg2 = "stuff");
+```
+
+then the wrapper functions should be
+
+```
+// SomeControl calls SomeControlV(label, value, 0, "stuff"). 
+SomeControl(label string, value int32) {
+    SomeControlV(label, value, 0, "stuff")
+}
+
+// SomeControlV does things (text possibly copied from imgui.h).
+SomeControlV(label string, value int32, optArg1 int32, optArg2 string) {
+    // ...
+}
+```
+
+The "idiomatic" function should have only the required parameters of the underlying function, and its comment specifies all the defaults, matching that of `imgui.h`.
+The "verbose" variant should require all the parameters of the underlying function.

WrapperConverter.go

@@ -41,6 +41,19 @@ func wrapInt32(goValue *int32) (wrapped *C.int, finisher func()) {
 	return
 }
 
+func wrapFloat(goValue *float32) (wrapped *C.float, finisher func()) {
+	if goValue != nil {
+		cValue := C.float(*goValue)
+		wrapped = &cValue
+		finisher = func() {
+			*goValue = float32(cValue)
+		}
+	} else {
+		finisher = func() {}
+	}
+	return
+}
+
 func wrapString(value string) (wrapped *C.char, finisher func()) {
 	wrapped = C.CString(value)
 	finisher = func() { C.free(unsafe.Pointer(wrapped)) } // nolint: gas

_examples/opengl3_example/main.go

@@ -1,10 +1,10 @@
 package main
 
 import (
+	"fmt"
 	"runtime"
 	"time"
 
-	"fmt"
 	"github.com/go-gl/gl/v3.2-core/gl"
 	"github.com/go-gl/glfw/v3.2/glfw"
 	"github.com/inkyblackness/imgui-go"

imgui.go

@@ -345,6 +345,54 @@ func EndCombo() {
 	C.iggEndCombo()
 }
 
+// DragFloatV creates a draggable slider for floats.
+func DragFloatV(label string, value *float32, speed, min, max float32, format string, power float32) bool {
+	labelArg, labelFin := wrapString(label)
+	defer labelFin()
+	valueArg, valueFin := wrapFloat(value)
+	defer valueFin()
+	formatArg, formatFin := wrapString(format)
+	defer formatFin()
+	return C.iggDragFloat(labelArg, valueArg, C.float(speed), C.float(min), C.float(max), formatArg, C.float(power)) != 0
+}
+
+// DragFloat calls DragFloatV(label, value, 1.0, 0.0, 0.0, "%.3f", 1.0).
+func DragFloat(label string, value *float32) bool {
+	return DragFloatV(label, value, 1.0, 0.0, 0.0, "%.3f", 1.0)
+}
+
+// DragIntV creates a draggable slider for integers.
+func DragIntV(label string, value *int32, speed float32, min, max int32, format string) bool {
+	labelArg, labelFin := wrapString(label)
+	defer labelFin()
+	valueArg, valueFin := wrapInt32(value)
+	defer valueFin()
+	formatArg, formatFin := wrapString(format)
+	defer formatFin()
+	return C.iggDragInt(labelArg, valueArg, C.float(speed), C.int(min), C.int(max), formatArg) != 0
+}
+
+// DragInt calls DragIntV(label, value, 1.0, 0, 0, "%d").
+func DragInt(label string, value *int32) bool {
+	return DragIntV(label, value, 1.0, 0, 0, "%d")
+}
+
+// SliderFloatV creates a slider for floats.
+func SliderFloatV(label string, value *float32, min, max float32, format string, power float32) bool {
+	labelArg, labelFin := wrapString(label)
+	defer labelFin()
+	valueArg, valueFin := wrapFloat(value)
+	defer valueFin()
+	formatArg, formatFin := wrapString(format)
+	defer formatFin()
+	return C.iggSliderFloat(labelArg, valueArg, C.float(min), C.float(max), formatArg, C.float(power)) != 0
+}
+
+// SliderFloat calls SliderIntV(label, value, min, max, "%.3f", 1.0).
+func SliderFloat(label string, value *float32, min, max float32) bool {
+	return SliderFloatV(label, value, min, max, "%.3f", 1.0)
+}
+
 // SliderIntV creates a slider for integers.
 func SliderIntV(label string, value *int32, min, max int32, format string) bool {
 	labelArg, labelFin := wrapString(label)

imguiWrapper.cpp

@@ -239,6 +239,21 @@ void iggEndCombo(void)
    ImGui::EndCombo();
 }
 
+IggBool iggDragFloat(char const *label, float *value, float speed, float min, float max, char const *format, float power)
+{
+    return ImGui::DragFloat(label, value, speed, min, max, format, power) ? 1 : 0;
+}
+
+IggBool iggDragInt(char const *label, int *value, float speed, int min, int max, char const *format)
+{
+    return ImGui::DragInt(label, value, speed, min, max, format) ? 1 : 0;
+}
+
+IggBool iggSliderFloat(char const *label, float *value, float minValue, float maxValue, char const *format, float power)
+{
+   return ImGui::SliderFloat(label, value, minValue, maxValue, format, power) ? 1 : 0;
+}
+
 IggBool iggSliderInt(char const *label, int *value, int minValue, int maxValue, char const *format)
 {
    return ImGui::SliderInt(label, value, minValue, maxValue, format) ? 1 : 0;

imguiWrapper.h

@@ -65,6 +65,10 @@ extern IggBool iggCheckbox(char const *label, IggBool *selected);
 extern IggBool iggBeginCombo(char const *label, char const *previewValue, int flags);
 extern void iggEndCombo(void);
 
+extern IggBool iggDragFloat(char const *label, float *value, float speed, float min, float max, char const *format, float power);
+extern IggBool iggDragInt(char const *label, int *value, float speed, int min, int max, char const *format);
+
+extern IggBool iggSliderFloat(char const *label, float *value, float minValue, float maxValue, char const *format, float power);
 extern IggBool iggSliderInt(char const *label, int *value, int minValue, int maxValue, char const *format);
 
 extern void iggSeparator(void);