ReignEngine: Set correct initial value for fog parameters

This fixes rendering issue of the model viewer in Alice's Mansion.

include/reign.h

@@ -42,6 +42,7 @@ enum RE_motion_state {
 };
 
 enum RE_fog_type {
+	RE_FOG_NONE             = 0,
 	RE_FOG_LINEAR           = 1,
 	RE_FOG_LIGHT_SCATTERING = 2,
 };

src/3d/debug.c

@@ -50,6 +50,7 @@ static const char *motion_state_name(enum RE_motion_state state)
 static const char *fog_type_name(enum RE_fog_type type)
 {
 	switch (type) {
+	case RE_FOG_NONE:             return "NONE";
 	case RE_FOG_LINEAR:           return "LINEAR";
 	case RE_FOG_LIGHT_SCATTERING: return "LIGHT_SCATTERING";
 	}
@@ -136,6 +137,8 @@ void RE_debug_print(struct sact_sprite *sp, int indent)
 
 	indent_printf(indent, "fog_type = %s,\n", fog_type_name(p->fog_type));
 	switch (p->fog_type) {
+	case RE_FOG_NONE:
+		break;
 	case RE_FOG_LINEAR:
 		indent_printf(indent, "fog_near = %f, fog_far = %f,\n", p->fog_near, p->fog_far);
 		indent_printf(indent, "fog_color = {r=%f, g=%f, b=%f},\n", SPREAD_VEC3(p->fog_color));

src/3d/reign.c

@@ -188,7 +188,10 @@ struct RE_plugin *RE_plugin_new(void)
 	plugin->aar = aar;
 	for (int i = 0; i < RE_NR_BACK_CGS; i++)
 		RE_back_cg_init(&plugin->back_cg[i]);
-	plugin->fog_type = RE_FOG_LINEAR;
+	plugin->fog_type = RE_FOG_NONE;
+	plugin->fog_near = 1.0;
+	plugin->fog_far = 10.0;
+	glm_vec3_one(plugin->fog_color);
 	return plugin;
 }
 

src/3d/renderer.c

@@ -806,6 +806,8 @@ void RE_render(struct sact_sprite *sp)
 	glUniform1f(r->shadow_bias, plugin->shadow_bias);
 	if (plugin->fog_mode) {
 		switch (plugin->fog_type) {
+		case RE_FOG_NONE:
+			break;
 		case RE_FOG_LINEAR:
 			glUniform1f(r->fog_near, plugin->fog_near);
 			glUniform1f(r->fog_far, plugin->fog_far);