From a9999ee10d25a99e292052d1f6c4af65c84f08b1 Mon Sep 17 00:00:00 2001
From: Louis Schmieder <dev@louis-schmieder.de>
Date: Thu, 21 May 2020 15:13:02 +0200
Subject: [PATCH] glm: add uniform functions to gl, add matrix rotation to glm

---
 vlib/gl/gl.v        | 19 +++++++++++++++
 vlib/glm/glm.v      | 57 +++++++++++++++++++++++++++++++++++++++++----
 vlib/glm/glm_test.v | 40 ++++++++++++++++++++++++++-----
 3 files changed, 106 insertions(+), 10 deletions(-)

diff --git a/vlib/gl/gl.v b/vlib/gl/gl.v
index 36820ccea7..c9ba9fe3d8 100644
--- a/vlib/gl/gl.v
+++ b/vlib/gl/gl.v
@@ -63,6 +63,9 @@ fn C.glGetUniformLocation() int
 fn C.glGetAttribLocation() int
 fn C.glBindAttribLocation()
 
+//Uniform functions
+fn C.glUniform1f()
+
 
 pub fn init_glad() {
 	ok := C.gladLoadGL()
@@ -292,4 +295,20 @@ pub fn generate_mipmap(typ int) {
 // set mat4 at uniform location
 pub fn set_mat4fv(loc, count int, transpose bool, val glm.Mat4) {
 	C.glUniformMatrix4fv(loc, count, transpose, val.data)
+}
+
+pub fn set_f32(loc int, val f32) {
+	C.glUniform1f(loc, val)
+}
+
+pub fn set_vec(loc int, x, y, z f32) {
+	C.glUniform3f(loc, x, y, z)
+}
+
+pub fn set_bool(loc int, val bool) {
+	if val {
+		set_f32(loc, 1)
+	} else {
+		set_f32(loc, 0)
+	}
 }
\ No newline at end of file
diff --git a/vlib/glm/glm.v b/vlib/glm/glm.v
index 202e8fdff3..59a67f47f2 100644
--- a/vlib/glm/glm.v
+++ b/vlib/glm/glm.v
@@ -65,7 +65,7 @@ pub fn (m Mat4) str() string {
 		}
 		for j in 0..4 {
 			val := m.data[i * 4 + j]
-			s += '${val:.2f} '
+			s += '${val:5.2f} '
 		}
 		if i != 3 {
 			s += '\n'
@@ -141,9 +141,9 @@ pub fn translate(m Mat4, v Vec3) Mat4 {
 	x := v.x
 	y := v.y
 	z := v.z
-	a00 := a[0]a01 := a[1]a02 := a[2]a03 := a[3]
-	a10 := a[4]a11 := a[5]a12 := a[6]a13 := a[7]
-	a20 := a[8]a21 := a[9]a22 := a[10]a23 := a[11]
+	a00 := a[0] a01 := a[1] a02 := a[2]  a03 := a[3]
+	a10 := a[4] a11 := a[5] a12 := a[6]  a13 := a[7]
+	a20 := a[8] a21 := a[9] a22 := a[10] a23 := a[11]
 	out[0] = a00 out[1] = a01 out[2] = a02 out[3] = a03
 	out[4] = a10 out[5] = a11 out[6] = a12 out[7] = a13
 	out[8] = a20 out[9] = a21 out[10] = a22 out[11] = a23
@@ -272,6 +272,55 @@ fn mult_mat_point(a Mat4, point Mat4) Mat4 {
 	return mat4(out)
 }
 
+pub fn rotate(angle f32, axis Vec3, src Mat4) Mat4 {
+	c := math.cos(angle)
+	s := math.sin(angle)
+	oneminusc := 1.0 - c
+
+	xy := axis.x * axis.y
+	yz := axis.y * axis.z
+	xz := axis.x * axis.z
+	xs := axis.x * s
+	ys := axis.y * s
+	zs := axis.z * s
+
+	f00 := axis.x * axis.x * oneminusc + c
+	f01 := xy * oneminusc + zs
+	f02 := xz * oneminusc - ys
+
+	f10 := xy * oneminusc-zs
+	f11 := axis.y * axis.y * oneminusc + c
+	f12 := yz * oneminusc + xs
+
+	f20 := xz * oneminusc + ys
+	f21 := yz * oneminusc - xs
+	f22 := axis.z  *axis.z * oneminusc + c
+
+	data := src.data
+
+	t00 := data[0] * f00 + data[4] * f01 + data[8] * f02
+	t01 := data[1] * f00 + data[5] * f01 + data[9] * f02
+	t02 := data[2] * f00 + data[6] * f01 + data[10] * f02
+	t03 := data[3] * f00 + data[7] * f01 + data[11] * f02
+
+	t10 := data[0] * f10 + data[4] * f11 + data[8] * f12
+	t11 := data[1] * f10 + data[5] * f11 + data[9] * f12
+	t12 := data[2] * f10 + data[6] * f11 + data[10] * f12
+	t13 := data[3] * f10 + data[7] * f11 + data[11] * f12
+
+	mut dest := src.data
+
+	dest[8] = data[0] * f20 + data[4] * f21 + data[8] * f22
+	dest[9] = data[1] * f20 + data[5] * f21 + data[9] * f22
+	dest[10] = data[2] * f20 + data[6] * f21 + data[10] * f22
+	dest[11] = data[3] * f20 + data[7] * f21 + data[11] * f22
+
+	dest[0] = t00	dest[1] = t01	dest[2] = t02	dest[3] = t03 
+	dest[4] = t10	dest[5] = t11	dest[6] = t12	dest[7] = t13
+
+	return mat4(dest)
+}
+
 // fn rotate_z(a *f32, rad f32) *f32 {
 pub fn rotate_z(m Mat4, rad f32) Mat4 {
 	a := m.data
diff --git a/vlib/glm/glm_test.v b/vlib/glm/glm_test.v
index 4604ebae38..90c65be4ff 100644
--- a/vlib/glm/glm_test.v
+++ b/vlib/glm/glm_test.v
@@ -67,6 +67,20 @@ fn test_rotate() {
 	$if debug {
 		println(m)
 	}
+
+	mut m1 := glm.identity()
+	mut m2 := glm.identity()
+
+	m1 = glm.rotate(1, glm.vec3(1, 0, 0), m1)
+	m2 = glm.rotate(1, glm.vec3(0, 1, 0), m2)
+
+	mut same := true
+	for i in 0..15 {
+		if m1.data[i] != m2.data[i] {
+			same = false
+		}
+	}
+	assert !same
 }
 
 fn test_translate() {
@@ -75,11 +89,25 @@ fn test_translate() {
 	$if debug {
 		println(m)
 	}
-	// TODO 
-	// mat4x4((1.000000, 0.000000, 0.000000, 0.000000),
-	// (0.000000, 1.000000, 0.000000, 0.000000),
-	// (0.000000, 0.000000, 1.000000, 0.000000),
-	// (0.000000, 0.000000, -0.500000, 1.000000))
+    assert m.data[0]  == 1.0 
+    assert m.data[1]  == 0.0
+    assert m.data[2]  == 0.0
+    assert m.data[3]  == 0.0
+    //
+    assert m.data[4]  == 0.0
+    assert m.data[5]  == 1.0
+    assert m.data[6]  == 0.0
+    assert m.data[7]  == 0.0
+    
+    assert m.data[8]  == 0.0
+    assert m.data[9]  == 0.0
+    assert m.data[10] == 1.0
+    assert m.data[11] == 0.0
+    //
+    assert m.data[12] == 0.0
+    assert m.data[13] == 0.0
+    assert m.data[14] == -0.5
+    assert m.data[15] == 1.0
 }
 
 fn test_mult() {
@@ -91,4 +119,4 @@ fn test_mult() {
 	for i in 0..15 {
 		assert a.data[i] == c.data[i]
 	}
-}
\ No newline at end of file
+}