Simplified shader system to only reference one file

include/sc_shading.h

@@ -2,17 +2,7 @@
  
    Example usage:
    
-     sc_shader_t *sh = sc_new_shader();
-     if (!sc_shader_attach_from_file(sh, "simple.vert", SC_VERTEX_SHADER) ||
-         !sc_shader_attach_from_file(sh, "simple.frag", SC_FRAGMENT_SHADER) ||
-         !sc_shader_finalize(sh))
-         sc_error_make_critical();
-
-   The above code can also be written in abbreviated form with the
-   help of a builtin factory function which will automatically load
-   *.vert files as vertex shaders and *.frag as fragment shaders.
-
-     sc_shader_t *sh = sc_shader_from_file("simple");
+     sc_shader_t *sh = sc_shader_from_file("simple.shader");
 
    Binding of shaders:
 
@@ -48,15 +38,11 @@ typedef struct _sc_shader sc_shader_t;
 sc_shader_t *sc_new_shader(void);
 
 /* simplified way to load shaders from files */
-sc_shader_t *sc_shader_from_file(const char *basename);
+sc_shader_t *sc_shader_from_file(const char *filename);
 
 /* frees a shader */
 void sc_free_shader(sc_shader_t *shader);
 
-/* attaches a new shader module */
-int sc_shader_attach_from_file(sc_shader_t *shader, const char *filename,
-                               int type);
-
 /* links all modules in the shader */
 int sc_shader_finalize(sc_shader_t *shader);
 

resources/shaders/loading.shader

@@ -0,0 +1,24 @@
+varying vec3 N, L;
+varying vec2 coord;
+uniform sampler2D sc_texture;
+
+#ifdef SC_VERTEX_SHADER
+void
+main(void)
+{
+    coord = sc_texcoord;
+    gl_Position = sc_mvp_matrix * vec4(sc_vertex, 1.0);
+    N = sc_normal_matrix * sc_normal;
+    L = vec3(0.3, 3.0, 10.0);
+}
+#endif
+
+#ifdef SC_FRAGMENT_SHADER
+void
+main(void)
+{
+    float intensity = max(0.0, dot(normalize(N), normalize(L)));
+    gl_FragColor = texture2D(sc_texture, coord);
+    gl_FragColor.rgb *= intensity;
+}
+#endif

resources/shaders/simple.frag → resources/shaders/simple.shader

@@ -6,6 +6,19 @@ varying vec3 coord;
 varying float vertex_light;
 uniform sampler2DArray sc_texture;
 
+#ifdef SC_VERTEX_SHADER
+void
+main(void)
+{
+    coord = sc_texcoord3;
+    vertex_light = sc_vertex_light;
+    gl_Position = sc_mvp_matrix * vec4(sc_vertex, 1.0);
+    normal = sc_normal_matrix * sc_normal;
+    half_vec = normalize(sc_vertex + sc_sun_direction) / 2.0;
+}
+#endif
+
+#ifdef SC_FRAGMENT_SHADER
 void
 main(void)
 {
@@ -22,3 +35,4 @@ main(void)
     color = color * clamp(darkness + (ambient + diffuse) * vertex_light, 0.0, 1.0);
     gl_FragColor = clamp(color, 0.0, 1.0);
 }
+#endif

src/game.c

@@ -83,11 +83,11 @@ init_game(void)
     sc_vec3_set(&cam->position, 0.0f, 30.0f, 100.0f);
     sc_camera_look_at(cam, 0.0f, 0.0f, 0.0f);
     loading_texture = sc_texture_from_resource("loading.png", 0);
-    loading_shader = sc_shader_from_file("loading");
+    loading_shader = sc_shader_from_file("loading.shader");
 
     /* this has to happen in the main thread before anything else */
     sc_init_blocks();
-    shader = sc_shader_from_file("simple");
+    shader = sc_shader_from_file("simple.shader");
 
     load_thread = sc_new_thread(init_game_in_thread, &done);
 

src/shading.c

@@ -22,6 +22,7 @@ struct _sc_shader {
 };
 
 static const sc_shader_t *current_shader;
+static int attach_from_file(sc_shader_t *, const char *, int);
 
 static GLenum
 convert_shader_type(int type)
@@ -45,28 +46,24 @@ sc_new_shader(void)
 }
 
 sc_shader_t *
-sc_shader_from_file(const char *basename)
-{
-#define ATTACH(Suffix, Type) do { \
-    size_t bn_len = strlen(basename); \
-    size_t s_len = strlen(Suffix); \
-    char *buf = sc_xmalloc(bn_len + s_len + 1); \
-    strcpy(buf, basename); \
-    strcpy(buf + bn_len, Suffix); \
-    if (!sc_shader_attach_from_file(rv, buf, Type)) { \
+sc_shader_from_file(const char *filename)
+{
+#define ATTACH(Type) do { \
+    if (!attach_from_file(rv, filename, Type)) { \
         if (sc_get_errno() != SC_ENOENT) \
             goto error; \
         sc_clear_error(); \
     } \
 } while (0)
 
     sc_shader_t *rv = sc_new_shader();
-    ATTACH(".vert", SC_VERTEX_SHADER);
-    ATTACH(".frag", SC_FRAGMENT_SHADER);
+    ATTACH(SC_VERTEX_SHADER);
+    ATTACH(SC_FRAGMENT_SHADER);
     if (sc_shader_finalize(rv))
         return rv;
 
 error:
+    sc_free_shader(rv);
     sc_error_make_critical();
     return NULL;
 }
@@ -131,6 +128,7 @@ read_shader_source(sc_strbuf_t *strbuf, sc_shader_t *shader,
 source_found:
     if (type) {
         char *common_file = sc_path_to_resource("shaders", "common.shader");
+        sc_strbuf_appendf(strbuf, "#version 120\n");
         switch (type) {
         case SC_VERTEX_SHADER:
             sc_strbuf_appendf(strbuf, "#define SC_VERTEX_SHADER\n");
@@ -182,9 +180,8 @@ set_shading_error(const sc_shader_t *shader, const char *info_log,
                  msg, source_info, info_log);
 }
 
-int
-sc_shader_attach_from_file(sc_shader_t *shader, const char *filename,
-                           int type)
+static int
+attach_from_file(sc_shader_t *shader, const char *filename, int type)
 {
     int success;
     char *path;