ADDED: shaders_basic_lighting

examples/shaders/rlights.h

@@ -0,0 +1,187 @@
+/**********************************************************************************************
+*
+*   raylib.lights - Some useful functions to deal with lights data
+*
+*   CONFIGURATION:
+*
+*   #define RLIGHTS_IMPLEMENTATION
+*       Generates the implementation of the library into the included file.
+*       If not defined, the library is in header only mode and can be included in other headers 
+*       or source files without problems. But only ONE file should hold the implementation.
+*
+*   LICENSE: zlib/libpng
+*
+*   Copyright (c) 2017-2019 Victor Fisac (@victorfisac) and Ramon Santamaria (@raysan5)
+*
+*   This software is provided "as-is", without any express or implied warranty. In no event
+*   will the authors be held liable for any damages arising from the use of this software.
+*
+*   Permission is granted to anyone to use this software for any purpose, including commercial
+*   applications, and to alter it and redistribute it freely, subject to the following restrictions:
+*
+*     1. The origin of this software must not be misrepresented; you must not claim that you
+*     wrote the original software. If you use this software in a product, an acknowledgment
+*     in the product documentation would be appreciated but is not required.
+*
+*     2. Altered source versions must be plainly marked as such, and must not be misrepresented
+*     as being the original software.
+*
+*     3. This notice may not be removed or altered from any source distribution.
+*
+**********************************************************************************************/
+
+#ifndef RLIGHTS_H
+#define RLIGHTS_H
+
+//----------------------------------------------------------------------------------
+// Defines and Macros
+//----------------------------------------------------------------------------------
+#define         MAX_LIGHTS            4         // Max dynamic lights supported by shader
+
+//----------------------------------------------------------------------------------
+// Types and Structures Definition
+//----------------------------------------------------------------------------------
+
+// Light data
+typedef struct {   
+    int type;
+    Vector3 position;
+    Vector3 target;
+    Color color;
+    bool enabled;
+    
+    // Shader locations
+    int enabledLoc;
+    int typeLoc;
+    int posLoc;
+    int targetLoc;
+    int colorLoc;
+} Light;
+
+// Light type
+typedef enum {
+    LIGHT_DIRECTIONAL,
+    LIGHT_POINT
+} LightType;
+
+#ifdef __cplusplus
+extern "C" {            // Prevents name mangling of functions
+#endif
+
+//----------------------------------------------------------------------------------
+// Global Variables Definition
+//----------------------------------------------------------------------------------
+int lightsCount = 0;    // Current amount of created lights
+
+//----------------------------------------------------------------------------------
+// Module Functions Declaration
+//----------------------------------------------------------------------------------
+Light CreateLight(int type, Vector3 position, Vector3 target, Color color, Shader shader);   // Create a light and get shader locations
+void UpdateLightValues(Shader shader, Light light);         // Send light properties to shader
+//void InitLightLocations(Shader shader, Light *light);     // Init light shader locations
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // RLIGHTS_H
+
+
+/***********************************************************************************
+*
+*   RLIGHTS IMPLEMENTATION
+*
+************************************************************************************/
+
+#if defined(RLIGHTS_IMPLEMENTATION)
+
+#include "raylib.h"
+
+//----------------------------------------------------------------------------------
+// Defines and Macros
+//----------------------------------------------------------------------------------
+// ...
+
+//----------------------------------------------------------------------------------
+// Types and Structures Definition
+//----------------------------------------------------------------------------------
+// ...
+
+//----------------------------------------------------------------------------------
+// Global Variables Definition
+//----------------------------------------------------------------------------------
+// ...
+
+//----------------------------------------------------------------------------------
+// Module specific Functions Declaration
+//----------------------------------------------------------------------------------
+// ...
+
+//----------------------------------------------------------------------------------
+// Module Functions Definition
+//----------------------------------------------------------------------------------
+
+// Create a light and get shader locations
+Light CreateLight(int type, Vector3 position, Vector3 target, Color color, Shader shader)
+{
+    Light light = { 0 };
+
+    if (lightsCount < MAX_LIGHTS)
+    {
+        light.enabled = true;
+        light.type = type;
+        light.position = position;
+        light.target = target;
+        light.color = color;
+
+        // TODO: Below code doesn't look good to me, 
+        // it assumes a specific shader naming and structure
+        // Probably this implementation could be improved
+        char enabledName[32] = "lights[x].enabled\0";
+        char typeName[32] = "lights[x].type\0";
+        char posName[32] = "lights[x].position\0";
+        char targetName[32] = "lights[x].target\0";
+        char colorName[32] = "lights[x].color\0";
+        enabledName[7] = '0' + lightsCount;
+        typeName[7] = '0' + lightsCount;
+        posName[7] = '0' + lightsCount;
+        targetName[7] = '0' + lightsCount;
+        colorName[7] = '0' + lightsCount;
+
+        light.enabledLoc = GetShaderLocation(shader, enabledName);
+        light.typeLoc = GetShaderLocation(shader, typeName);
+        light.posLoc = GetShaderLocation(shader, posName);
+        light.targetLoc = GetShaderLocation(shader, targetName);
+        light.colorLoc = GetShaderLocation(shader, colorName);
+
+        UpdateLightValues(shader, light);
+        
+        lightsCount++;
+    }
+
+    return light;
+}
+
+// Send light properties to shader
+// NOTE: Light shader locations should be available 
+void UpdateLightValues(Shader shader, Light light)
+{
+    // Send to shader light enabled state and type
+    SetShaderValue(shader, light.enabledLoc, &light.enabled, UNIFORM_INT);
+    SetShaderValue(shader, light.typeLoc, &light.type, UNIFORM_INT);
+
+    // Send to shader light position values
+    float position[3] = { light.position.x, light.position.y, light.position.z };
+    SetShaderValue(shader, light.posLoc, position, UNIFORM_VEC3);
+
+    // Send to shader light target position values
+    float target[3] = { light.target.x, light.target.y, light.target.z };
+    SetShaderValue(shader, light.targetLoc, target, UNIFORM_VEC3);
+
+    // Send to shader light color values
+    float color[4] = { (float)light.color.r/(float)255, (float)light.color.g/(float)255, 
+                       (float)light.color.b/(float)255, (float)light.color.a/(float)255 };
+    SetShaderValue(shader, light.colorLoc, color, UNIFORM_VEC4);
+}
+
+#endif // RLIGHTS_IMPLEMENTATION