From f0b4f2d46e3bfb9c3bd36a857283e551f2d6d3fc Mon Sep 17 00:00:00 2001
From: Emmanuel Benoit <tseeker@nocternity.net>
Date: Sat, 30 Sep 2017 11:23:14 +0200
Subject: [PATCH] Raymarcher + automatic load

---
 Makefile        |  4 +--
 main.cc         | 66 +++++++++++++++++++++++++++++++++++++++++++++++++
 map.glsl        |  4 +++
 raymarcher.glsl | 23 +++++++++--------
 4 files changed, 84 insertions(+), 13 deletions(-)
 create mode 100644 map.glsl

diff --git a/Makefile b/Makefile
index 5dab264..00327a3 100644
--- a/Makefile
+++ b/Makefile
@@ -4,9 +4,7 @@ CPPFLAGS += -I. -Iimgui -Iglm \
 	    -DREAL_BUILD -DGLM_ENABLE_EXPERIMENTAL
 LIBS += $(shell sdl2-config --libs) -lGL -lGLEW -ldl
 
-FILEDUMPS = \
-	    fd-raymarch-header.glsl.h \
-	    fd-raymarcher.glsl.h
+FILEDUMPS =
 
 IMGUI = imgui.o imgui_demo.o imgui_draw.o
 DEMO = \
diff --git a/main.cc b/main.cc
index 6ad047d..6c41d4e 100644
--- a/main.cc
+++ b/main.cc
@@ -18,6 +18,8 @@ struct T_Main
 	SDL_Window * window;
 	SDL_GLContext gl;
 	T_FilesWatcher watcher;
+	T_WatchedFiles shaderFiles;
+	GLuint prog;
 	std::string loadError;
 
 	bool done = false;
@@ -29,11 +31,16 @@ struct T_Main
 	void handleCapture( );
 	void makeUI( );
 	void render( );
+
+	void loadProgram( );
 };
 
 /*----------------------------------------------------------------------------*/
 
 T_Main::T_Main( )
+	: shaderFiles( watcher , [this] {
+			this->loadProgram( );
+		} )
 {
 	SDL_Init( SDL_INIT_VIDEO | SDL_INIT_TIMER );
 
@@ -52,6 +59,8 @@ T_Main::T_Main( )
 	gl = SDL_GL_CreateContext( window );
 	glewInit();
 	ImGui_ImplSdl_Init( window );
+
+	loadProgram( );
 }
 
 void T_Main::mainLoop( )
@@ -148,6 +157,34 @@ void T_Main::render( )
 
 	// FIXME draw the fuck
 	//project->render( );
+	if ( prog != 0 ) {
+		glUseProgram( prog );
+
+		enum {
+			U_TIME			= 0 ,
+			U_RESOLUTION		= 1 ,
+			U_CAM_POS		= 2 ,
+			U_LOOK_AT		= 3 ,
+			U_CAM_UP		= 4 ,
+			U_NEAR_PLANE		= 5 ,
+			U_LIGHT_DIR		= 6 ,
+			U_RENDER		= 7 ,
+		};
+
+		auto const& dspSize( ImGui::GetIO( ).DisplaySize );
+		glUniform1f( U_TIME , 0 );
+		glUniform2f( U_RESOLUTION , dspSize.x , dspSize.y );
+
+		glUniform3f( U_CAM_POS , 0 , 0 , -15 );
+		glUniform3f( U_LOOK_AT , 0 , 0 , 0 );
+		glUniform3f( U_CAM_UP , 0 , 1 , 0 );
+		glUniform1f( U_NEAR_PLANE , 1 );
+
+		glUniform3f( U_LIGHT_DIR , 0 , 1 , 1 );
+		glUniform4f( U_RENDER , 128 , 0.9 , 0.001 , 100 );
+
+		glRectf( -1, -1 , 1 , 1 );
+	}
 
 	glUseProgram( 0 );
 	ImGui::Render( );
@@ -155,6 +192,35 @@ void T_Main::render( )
 }
 
 
+void T_Main::loadProgram( )
+{
+	std::vector< std::string > errors;
+
+	if ( prog != 0 ) {
+		glDeleteProgram( prog );
+		prog = 0;
+	}
+
+	shaderFiles.clear( );
+	shaderFiles.watch( "raymarch-header.glsl" );
+	shaderFiles.watch( "map.glsl" );
+	shaderFiles.watch( "raymarcher.glsl" );
+
+	T_ShaderCode shader( 3 );
+	shader.loadPart( 0 , "raymarch-header.glsl" , errors );
+	shader.loadPart( 1 , "map.glsl" , errors );
+	shader.loadPart( 2 , "raymarcher.glsl" , errors );
+
+	prog = shader.createProgram( GL_FRAGMENT_SHADER , errors );
+
+	if ( errors.size( ) != 0 ) {
+		for ( auto const& str : errors ) {
+			printf( "ERR: %s\n" , str.c_str( ) );
+		}
+	}
+}
+
+
 /*============================================================================*/
 
 int main( int , char** )
diff --git a/map.glsl b/map.glsl
new file mode 100644
index 0000000..a62fc36
--- /dev/null
+++ b/map.glsl
@@ -0,0 +1,4 @@
+vec2 map( vec3 pos )
+{
+	return vec2( length( pos ) - 1. , 0. );
+}
diff --git a/raymarcher.glsl b/raymarcher.glsl
index 312aebf..9ef9cad 100644
--- a/raymarcher.glsl
+++ b/raymarcher.glsl
@@ -49,8 +49,6 @@ void main( )
 {
 	setCamFromUniforms( );
 
-	int dispMode = ( u_DebugFeatures.x >> 3 ) & 3;
-
 	vec2 uv = ( gl_FragCoord.xy / u_Resolution ) * 2 - 1;
 	vec3 camDir = normalize( lookAt - camPos );
 	vec3 side = normalize( cross( camUp , camDir ) );
@@ -62,14 +60,19 @@ void main( )
 	vec3 r = march( camPos , rayDir , int( u_Render.x ) , u_Render.y );
 	vec3 hitPos = camPos + rayDir * r.x;
 
-	vec3 bc = vec3( 1. );
-	vec3 hvec = normalize( rayDir - u_LightDir ) ,
-	     norm = getNormal( hitPos );
-	float ndotl = dot( norm , -normalize( u_LightDir ) ) ,
-	      ndoth = dot( norm , hvec );
-	float si = pow( clamp( ndoth , 0 , 1 ) , 4 ) ,
-	      di = .6 + .3 * clamp( ndotl , 0 , 1 );
-	bc = mix( bc * di , vec3( 1. ) , si );
+	vec3 bc;
+	if ( r.y >= 0. ) {
+		bc = vec3( 1. , 1. , 0. );
+		vec3 hvec = normalize( rayDir - u_LightDir ) ,
+		     norm = getNormal( hitPos );
+		float ndotl = dot( norm , -normalize( u_LightDir ) ) ,
+		      ndoth = dot( norm , hvec );
+		float si = pow( clamp( ndoth , 0 , 1 ) , 4 ) ,
+		      di = .6 + .3 * clamp( ndotl , 0 , 1 );
+		bc = mix( bc * di , vec3( 1. ) , si );
+	} else {
+		bc = vec3( 0. );
+	}
 
 	color = vec4( bc , 1 );