rename basic shader to character

add character shadow
make animation play twice as fast when sprinting

src/main.cpp

@@ -36,6 +36,7 @@ static SDL_Window *window;
 static R_Texture  framebuffer;
 
 static R_Texture player_texture;
+static R_Texture character_shadow_texture;
 static R_Texture tile_textures_atlas;
 static R_Texture tile_textures_atlas_imgui;
 
@@ -915,6 +916,12 @@ static bool init_resources() {
         return false;
     }
 
+    character_shadow_texture = create_texture("characters/shadow.png");
+    if (!character_shadow_texture) {
+        log_error("Failed to create shader texture.");
+        return false;
+    }
+
     if (!recreate_tile_textures()) {
         log_error("Failed to create tile textures.");
         return false;
@@ -1438,7 +1445,7 @@ static void update_state_game() {
     const bool *keyboard_state = SDL_GetKeyboardState(NULL);
 
     if (player.is_moving) {
-        player.animation_time += delta_time;
+        player.animation_time += delta_time * (keyboard_state[SDL_SCANCODE_LSHIFT] ? 2 : 1);
 
         vec2 leftover_movement = vec2(player.target_position) - player.visual_position;
         vec2 movement = clamp(min(vec2(0, 0), leftover_movement), normalize(leftover_movement) * (delta_t * character_speed * (keyboard_state[SDL_SCANCODE_LSHIFT] ? 2.0f : 1.0f)), max(vec2(0, 0), leftover_movement));
@@ -1478,7 +1485,8 @@ static void render_game() {
         {
             ZoneScopedN("player_instance_buffer");
 
-            Uint64 variation_index = (player.animation_time / (100 * SDL_NS_PER_MS)) % 4;
+            Uint64 ns_per_variation = (1.0f / (character_speed * 2)) * SDL_NS_PER_SECOND; 
+            Uint64 variation_index = (player.animation_time / (ns_per_variation)) % 4;
 
             player_instance.pos              = player.visual_position;
             player_instance.sprite_selection = variation_index << 16 | player.direction;
@@ -1555,7 +1563,20 @@ static void render_game() {
 
     {
         ZoneScopedN("Draw Player");
-        renderer_frame_set_shader(R_SHADER_BASIC);
+        renderer_frame_set_shader(R_SHADER_CHARACTER_SHADOW);
+        renderer_frame_draw(vertex_buffer, index_buffer, player_instance_buffer, 6, 1, &(R_Draw_Resources){
+            .vertex_uniform_buffers = (R_Buffer[]){ view_projection_matrix_buffer },
+
+            .num_vertex_uniform_buffers = 1,
+
+            .fragment_sampled_textures = (R_Texture[]){ character_shadow_texture },
+            .fragment_uniform_buffers  = (R_Buffer[]){ tint_color_buffer },
+
+            .num_fragment_sampled_textures = 1,
+            .num_fragment_uniform_buffers  = 1,
+        });
+
+        renderer_frame_set_shader(R_SHADER_CHARACTER);
         renderer_frame_draw(vertex_buffer, index_buffer, player_instance_buffer, 6, 1, &(R_Draw_Resources){
             .vertex_uniform_buffers = (R_Buffer[]){ view_projection_matrix_buffer },