raylib/examples/models/models_draw_cube_texture.c

/*******************************************************************************************
*
*   raylib [models] example - Draw textured cube
*
*   Example originally created with raylib 4.5, last time updated with raylib 4.5
*
*   Example licensed under an unmodified zlib/libpng license, which is an OSI-certified,
*   BSD-like license that allows static linking with closed source software
*
*   Copyright (c) 2022-2023 Ramon Santamaria (@raysan5)
*
********************************************************************************************/

#include "raylib.h"

#include "rlgl.h"       // Required to define vertex data (immediate-mode style)

//------------------------------------------------------------------------------------
// Custom Functions Declaration
//------------------------------------------------------------------------------------
void DrawCubeTexture(Texture2D texture, Vector3 position, float width, float height, float length, Color color); // Draw cube textured
void DrawCubeTextureRec(Texture2D texture, Rectangle source, Vector3 position, float width, float height, float length, Color color); // Draw cube with a region of a texture

//------------------------------------------------------------------------------------
// Program main entry point
//------------------------------------------------------------------------------------
int main(void)
{
    // Initialization
    //--------------------------------------------------------------------------------------
    const int screenWidth = 800;
    const int screenHeight = 450;

    InitWindow(screenWidth, screenHeight, "raylib [models] example - draw cube texture");

    // Define the camera to look into our 3d world
    Camera camera = { 0 };
    camera.position = (Vector3){ 0.0f, 10.0f, 10.0f };
    camera.target = (Vector3){ 0.0f, 0.0f, 0.0f };
    camera.up = (Vector3){ 0.0f, 1.0f, 0.0f };
    camera.fovy = 45.0f;
    camera.projection = CAMERA_PERSPECTIVE;
    
    // Load texture to be applied to the cubes sides
    Texture2D texture = LoadTexture("resources/cubicmap_atlas.png");

    SetTargetFPS(60);               // Set our game to run at 60 frames-per-second
    //--------------------------------------------------------------------------------------

    // Main game loop
    while (!WindowShouldClose())    // Detect window close button or ESC key
    {
        // Update
        //----------------------------------------------------------------------------------
        // TODO: Update your variables here
        //----------------------------------------------------------------------------------

        // Draw
        //----------------------------------------------------------------------------------
        BeginDrawing();

            ClearBackground(RAYWHITE);

            BeginMode3D(camera);

                // Draw cube with an applied texture
                DrawCubeTexture(texture, (Vector3){ -2.0f, 2.0f, 0.0f }, 2.0f, 4.0f, 2.0f, WHITE);

                // Draw cube with an applied texture, but only a defined rectangle piece of the texture
                DrawCubeTextureRec(texture, (Rectangle){ 0, texture.height/2, texture.width/2, texture.height/2 }, 
                    (Vector3){ 2.0f, 1.0f, 0.0f }, 2.0f, 2.0f, 2.0f, WHITE);

                DrawGrid(10, 1.0f);        // Draw a grid

            EndMode3D();

            DrawFPS(10, 10);

        EndDrawing();
        //----------------------------------------------------------------------------------
    }

    // De-Initialization
    //--------------------------------------------------------------------------------------
    UnloadTexture(texture); // Unload texture
    
    CloseWindow();          // Close window and OpenGL context
    //--------------------------------------------------------------------------------------

    return 0;
}

//------------------------------------------------------------------------------------
// Custom Functions Definition
//------------------------------------------------------------------------------------
// Draw cube textured
// NOTE: Cube position is the center position
void DrawCubeTexture(Texture2D texture, Vector3 position, float width, float height, float length, Color color)
{
    float x = position.x;
    float y = position.y;
    float z = position.z;

    // Set desired texture to be enabled while drawing following vertex data
    rlSetTexture(texture.id);

    // Vertex data transformation can be defined with the commented lines,
    // but in this example we calculate the transformed vertex data directly when calling rlVertex3f()
    //rlPushMatrix();
        // NOTE: Transformation is applied in inverse order (scale -> rotate -> translate)
        //rlTranslatef(2.0f, 0.0f, 0.0f);
        //rlRotatef(45, 0, 1, 0);
        //rlScalef(2.0f, 2.0f, 2.0f);

        rlBegin(RL_QUADS);
            rlColor4ub(color.r, color.g, color.b, color.a);
            // Front Face
            rlNormal3f(0.0f, 0.0f, 1.0f);       // Normal Pointing Towards Viewer
            rlTexCoord2f(0.0f, 0.0f); rlVertex3f(x - width/2, y - height/2, z + length/2);  // Bottom Left Of The Texture and Quad
            rlTexCoord2f(1.0f, 0.0f); rlVertex3f(x + width/2, y - height/2, z + length/2);  // Bottom Right Of The Texture and Quad
            rlTexCoord2f(1.0f, 1.0f); rlVertex3f(x + width/2, y + height/2, z + length/2);  // Top Right Of The Texture and Quad
            rlTexCoord2f(0.0f, 1.0f); rlVertex3f(x - width/2, y + height/2, z + length/2);  // Top Left Of The Texture and Quad
            // Back Face
            rlNormal3f(0.0f, 0.0f, - 1.0f);     // Normal Pointing Away From Viewer
            rlTexCoord2f(1.0f, 0.0f); rlVertex3f(x - width/2, y - height/2, z - length/2);  // Bottom Right Of The Texture and Quad
            rlTexCoord2f(1.0f, 1.0f); rlVertex3f(x - width/2, y + height/2, z - length/2);  // Top Right Of The Texture and Quad
            rlTexCoord2f(0.0f, 1.0f); rlVertex3f(x + width/2, y + height/2, z - length/2);  // Top Left Of The Texture and Quad
            rlTexCoord2f(0.0f, 0.0f); rlVertex3f(x + width/2, y - height/2, z - length/2);  // Bottom Left Of The Texture and Quad
            // Top Face
            rlNormal3f(0.0f, 1.0f, 0.0f);       // Normal Pointing Up
            rlTexCoord2f(0.0f, 1.0f); rlVertex3f(x - width/2, y + height/2, z - length/2);  // Top Left Of The Texture and Quad
            rlTexCoord2f(0.0f, 0.0f); rlVertex3f(x - width/2, y + height/2, z + length/2);  // Bottom Left Of The Texture and Quad
            rlTexCoord2f(1.0f, 0.0f); rlVertex3f(x + width/2, y + height/2, z + length/2);  // Bottom Right Of The Texture and Quad
            rlTexCoord2f(1.0f, 1.0f); rlVertex3f(x + width/2, y + height/2, z - length/2);  // Top Right Of The Texture and Quad
            // Bottom Face
            rlNormal3f(0.0f, - 1.0f, 0.0f);     // Normal Pointing Down
            rlTexCoord2f(1.0f, 1.0f); rlVertex3f(x - width/2, y - height/2, z - length/2);  // Top Right Of The Texture and Quad
            rlTexCoord2f(0.0f, 1.0f); rlVertex3f(x + width/2, y - height/2, z - length/2);  // Top Left Of The Texture and Quad
            rlTexCoord2f(0.0f, 0.0f); rlVertex3f(x + width/2, y - height/2, z + length/2);  // Bottom Left Of The Texture and Quad
            rlTexCoord2f(1.0f, 0.0f); rlVertex3f(x - width/2, y - height/2, z + length/2);  // Bottom Right Of The Texture and Quad
            // Right face
            rlNormal3f(1.0f, 0.0f, 0.0f);       // Normal Pointing Right
            rlTexCoord2f(1.0f, 0.0f); rlVertex3f(x + width/2, y - height/2, z - length/2);  // Bottom Right Of The Texture and Quad
            rlTexCoord2f(1.0f, 1.0f); rlVertex3f(x + width/2, y + height/2, z - length/2);  // Top Right Of The Texture and Quad
            rlTexCoord2f(0.0f, 1.0f); rlVertex3f(x + width/2, y + height/2, z + length/2);  // Top Left Of The Texture and Quad
            rlTexCoord2f(0.0f, 0.0f); rlVertex3f(x + width/2, y - height/2, z + length/2);  // Bottom Left Of The Texture and Quad
            // Left Face
            rlNormal3f( - 1.0f, 0.0f, 0.0f);    // Normal Pointing Left
            rlTexCoord2f(0.0f, 0.0f); rlVertex3f(x - width/2, y - height/2, z - length/2);  // Bottom Left Of The Texture and Quad
            rlTexCoord2f(1.0f, 0.0f); rlVertex3f(x - width/2, y - height/2, z + length/2);  // Bottom Right Of The Texture and Quad
            rlTexCoord2f(1.0f, 1.0f); rlVertex3f(x - width/2, y + height/2, z + length/2);  // Top Right Of The Texture and Quad
            rlTexCoord2f(0.0f, 1.0f); rlVertex3f(x - width/2, y + height/2, z - length/2);  // Top Left Of The Texture and Quad
        rlEnd();
    //rlPopMatrix();

    rlSetTexture(0);
}

// Draw cube with texture piece applied to all faces
void DrawCubeTextureRec(Texture2D texture, Rectangle source, Vector3 position, float width, float height, float length, Color color)
{
    float x = position.x;
    float y = position.y;
    float z = position.z;
    float texWidth = (float)texture.width;
    float texHeight = (float)texture.height;

    // Set desired texture to be enabled while drawing following vertex data
    rlSetTexture(texture.id);

    // We calculate the normalized texture coordinates for the desired texture-source-rectangle
    // It means converting from (tex.width, tex.height) coordinates to [0.0f, 1.0f] equivalent 
    rlBegin(RL_QUADS);
        rlColor4ub(color.r, color.g, color.b, color.a);

        // Front face
        rlNormal3f(0.0f, 0.0f, 1.0f);
        rlTexCoord2f(source.x/texWidth, (source.y + source.height)/texHeight);
        rlVertex3f(x - width/2, y - height/2, z + length/2);
        rlTexCoord2f((source.x + source.width)/texWidth, (source.y + source.height)/texHeight);
        rlVertex3f(x + width/2, y - height/2, z + length/2);
        rlTexCoord2f((source.x + source.width)/texWidth, source.y/texHeight);
        rlVertex3f(x + width/2, y + height/2, z + length/2);
        rlTexCoord2f(source.x/texWidth, source.y/texHeight);
        rlVertex3f(x - width/2, y + height/2, z + length/2);

        // Back face
        rlNormal3f(0.0f, 0.0f, - 1.0f);
        rlTexCoord2f((source.x + source.width)/texWidth, (source.y + source.height)/texHeight);
        rlVertex3f(x - width/2, y - height/2, z - length/2);
        rlTexCoord2f((source.x + source.width)/texWidth, source.y/texHeight);
        rlVertex3f(x - width/2, y + height/2, z - length/2);
        rlTexCoord2f(source.x/texWidth, source.y/texHeight);
        rlVertex3f(x + width/2, y + height/2, z - length/2);
        rlTexCoord2f(source.x/texWidth, (source.y + source.height)/texHeight);
        rlVertex3f(x + width/2, y - height/2, z - length/2);

        // Top face
        rlNormal3f(0.0f, 1.0f, 0.0f);
        rlTexCoord2f(source.x/texWidth, source.y/texHeight);
        rlVertex3f(x - width/2, y + height/2, z - length/2);
        rlTexCoord2f(source.x/texWidth, (source.y + source.height)/texHeight);
        rlVertex3f(x - width/2, y + height/2, z + length/2);
        rlTexCoord2f((source.x + source.width)/texWidth, (source.y + source.height)/texHeight);
        rlVertex3f(x + width/2, y + height/2, z + length/2);
        rlTexCoord2f((source.x + source.width)/texWidth, source.y/texHeight);
        rlVertex3f(x + width/2, y + height/2, z - length/2);

        // Bottom face
        rlNormal3f(0.0f, - 1.0f, 0.0f);
        rlTexCoord2f((source.x + source.width)/texWidth, source.y/texHeight);
        rlVertex3f(x - width/2, y - height/2, z - length/2);
        rlTexCoord2f(source.x/texWidth, source.y/texHeight);
        rlVertex3f(x + width/2, y - height/2, z - length/2);
        rlTexCoord2f(source.x/texWidth, (source.y + source.height)/texHeight);
        rlVertex3f(x + width/2, y - height/2, z + length/2);
        rlTexCoord2f((source.x + source.width)/texWidth, (source.y + source.height)/texHeight);
        rlVertex3f(x - width/2, y - height/2, z + length/2);

        // Right face
        rlNormal3f(1.0f, 0.0f, 0.0f);
        rlTexCoord2f((source.x + source.width)/texWidth, (source.y + source.height)/texHeight);
        rlVertex3f(x + width/2, y - height/2, z - length/2);
        rlTexCoord2f((source.x + source.width)/texWidth, source.y/texHeight);
        rlVertex3f(x + width/2, y + height/2, z - length/2);
        rlTexCoord2f(source.x/texWidth, source.y/texHeight);
        rlVertex3f(x + width/2, y + height/2, z + length/2);
        rlTexCoord2f(source.x/texWidth, (source.y + source.height)/texHeight);
        rlVertex3f(x + width/2, y - height/2, z + length/2);

        // Left face
        rlNormal3f( - 1.0f, 0.0f, 0.0f);
        rlTexCoord2f(source.x/texWidth, (source.y + source.height)/texHeight);
        rlVertex3f(x - width/2, y - height/2, z - length/2);
        rlTexCoord2f((source.x + source.width)/texWidth, (source.y + source.height)/texHeight);
        rlVertex3f(x - width/2, y - height/2, z + length/2);
        rlTexCoord2f((source.x + source.width)/texWidth, source.y/texHeight);
        rlVertex3f(x - width/2, y + height/2, z + length/2);
        rlTexCoord2f(source.x/texWidth, source.y/texHeight);
        rlVertex3f(x - width/2, y + height/2, z - length/2);

    rlEnd();

    rlSetTexture(0);
}