add arrows to bow production

isotest/bits/elem_lib.v

@@ -61,6 +61,17 @@ fn init_elem_lib() {
 		bits_ctx.elem_lib["textile"] = el
 	}
 
+	{
+		mut el := new_elem()
+		el.name = "iron" // XXX wrought iron
+		el.elem_type = .iron
+		el.density = 7870 // wiki (iron)
+		el.flameable = false
+		el.notes = "wrought iron"
+
+		bits_ctx.elem_lib["iron"] = el
+	}
+
 	{
 		mut el := new_elem()
 		el.name = "water"

isotest/bits/elems.v

@@ -69,6 +69,8 @@ mut:
 	// XXX?
 	aggregate_state AggregateState
 
+	notes string
+
 	// when
 	//when_crushed_fn fn()
 	//when_crushed_effects []Effect

isotest/bits/main.v

@@ -52,6 +52,20 @@ fn test_bow() {
 	println("bow new bits volume: ${bow.bits_volume()}")
 	println("bow new volume: ${bow.volume()}")
 
+	// XXX test arrows
+
+	mut arrow := new_object()
+
+	// Arrowhead weight: 200g
+	// Arrow shaft size: 1x1x50 cm
+
+	arrow.mat_info.add_elem_from_mass(0.2, bits_ctx.elem_lib["iron"])
+	arrow.mat_info.add_elem_from_size(
+		cm_to_m(1), cm_to_m(1), cm_to_m(50), bits_ctx.elem_lib["wood"])
+
+	println("arrow new bits volume: ${arrow.bits_volume()}")
+	println("arrow new volume: ${arrow.volume()}")
+
 	println("bits: done test_bow")
 }
 

isotest/bits/material.v

@@ -88,6 +88,19 @@ pub fn (mut mi MaterialInfo) add_elem_from_volume(vol f32, elem &Elem) {
 	mi.add_elem(vol_bits, elem)
 }
 
+// From volume mass/weight
+pub fn (mut mi MaterialInfo) add_elem_from_mass(mass f32, elem &Elem) {
+	println("MaterialInfo add_elem_from_mass: mass: $mass, elem.name: $elem.name")
+
+	vol := mass / f32(elem.density)
+
+	vol_bits := m3_to_bits(vol)
+
+	println("vol: $vol, vol_bits: $vol_bits")
+
+	mi.add_elem(vol_bits, elem)
+}
+
 //fn (mut mi MaterialInfo) add_elem_from_size(size [3]f32, elem &Elem) {
 //fn (mut pi PartsInfo) add_elem_from_size(size []f32, elem &Elem) {
 //	println("PartsInfo add_elem_from_size: $size, elem.name: $elem.name")

isotest/bits/todo.txt

@@ -8,4 +8,8 @@ test 2:
 	destroy the wall or part of the wall to crushed stone
 
 test 3:
-	produce medieval bow
+	produce medieval bow
+
+test 4:
+	? generic bow
+	  - data/model reuse

isotest/bits/util.v

@@ -24,3 +24,13 @@ fn m3_to_bits(m3 f32) int {
 	//return int(m3 * 1000 / (math.powf(c_bit_size, 3)))
 	return int(m3 * c_bits_in_m3)
 }
+
+[inline]
+fn m_to_cm(m f32) f32 {
+	return m * 100.0
+}
+
+[inline]
+fn cm_to_m(cm f32) f32 {
+	return cm / 100.0
+}

isotest/calc_mats.py

@@ -0,0 +1,25 @@
+#!/bin/env python
+
+import sys
+
+if len(sys.argv) < 3:
+    print("usage: %s mat_density (kg/m3) model_mass (kg)" % sys.argv[0])
+    exit()
+
+mat_density = int(sys.argv[1])
+
+model_mass = float(sys.argv[2])
+
+mat_volume = model_mass / mat_density
+result_bits = mat_volume / (1.0/100) # 10x10x10
+
+print("mat_density (kg/m3):", mat_density)
+print("model_mass (kg):", model_mass)
+print("")
+print("raw mat_volume:", mat_volume)
+print("")
+print("result:")
+print("mat_volume (m3):", f'{mat_volume:f}')
+print("result_bits:", result_bits)
+print("")
+print("done")