From 232035b7e24d2a49a472c28b326f2227af11963d Mon Sep 17 00:00:00 2001
From: Tomasz Kramkowski <tk@the-tk.com>
Date: Thu, 3 May 2018 14:12:44 +0100
Subject: Animate the light position around the cube

---
 faqe.c    | 9 ++++++++-
 vert.glsl | 3 +--
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/faqe.c b/faqe.c
index 3b81e24..e51aaf0 100644
--- a/faqe.c
+++ b/faqe.c
@@ -37,7 +37,7 @@ int main(int argc, char **argv)
 	SDL_GLContext *glc;
 	GLuint prog;
 	struct {
-		GLint model, view, proj, tex;
+		GLint model, view, proj, tex, light;
 	} uni;
 	FILE *cube_file;
 	struct fmd cube_fmd;
@@ -46,6 +46,7 @@ int main(int argc, char **argv)
 	struct {
 		bool w, a, s, d, spc, lct;
 	} key = { 0 };
+	vec4 lipos;
 	float tlast;
 
 	setprogname(argc >= 1 && argv[0] != NULL ? argv[0] : "faqe");
@@ -91,6 +92,7 @@ int main(int argc, char **argv)
 			{ "view", &uni.view },
 			{ "proj", &uni.proj },
 			{ "tex", &uni.tex },
+			{ "light", &uni.light },
 			{ 0 },
 		});
 
@@ -164,6 +166,10 @@ int main(int argc, char **argv)
 
 		camera_lookat(view, &cam);
 
+		lipos[0] = 3.0 * cosf(tnow / 10) * cosf(tnow / 20);
+		lipos[1] = 3.0 * sinf(tnow / 10);
+		lipos[2] = 3.0 * cosf(tnow / 10) * sinf(tnow / 20);
+
 		gl_clearcolor(0.2, 0.3, 0.3, 1.0);
 		gl_clear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 		mat4x4_identity(model);
@@ -171,6 +177,7 @@ int main(int argc, char **argv)
 		gl_prog_use(prog);
 		gl_uni_setm4fv(uni.view, 1, GL_FALSE, view[0]);
 		gl_uni_setm4fv(uni.model, 1, GL_FALSE, model[0]);
+		gl_uni_set3fv(uni.light, 1, lipos);
 		model_render(&cube_model);
 		gl_va_bind(0);
 
diff --git a/vert.glsl b/vert.glsl
index 9fea064..19469a4 100644
--- a/vert.glsl
+++ b/vert.glsl
@@ -15,11 +15,10 @@ out vec3 lipos;
 uniform mat4 model;
 uniform mat4 view;
 uniform mat4 proj;
+uniform vec3 light;
 
 void main()
 {
-	vec3 light = vec3(1.2, 1.0, 2.0);
-
 	gl_Position = proj * view * model * vec4(pos, 1.0);
 	fpos = vec3(view * model * vec4(pos, 1.0));
 	fuv = uv;
-- 
cgit v1.2.3-54-g00ecf