SDL_RenderCopy not rendering (Isn't NULL, none SDL/IMG Error too)












1















I'm trying to make a simple Snake game. The self collision and a lot of things aren't ready. The problem is: Even with no errors, running just fine, changing "close()" to "endGame()" and reverting, rebuilding the entire program, i could not render anything with SDL_RenderCopy. You will see many unnecessary things in my code and some Brazilian-Portuguese comments, prepare yourself.



The image is a 16x16 png spritesheet, using the color #ff00ff as ColorKey. There are only 4 sprites in this spritesheet, respectively: Apple, Snake's Body, Snake's Head and Snake's Tail (still unused).



Whole code:



#include <iostream>

#include <SDL2/SDL.h>

#include <SDL2/SDL_image.h>

#include <stdlib.h>

#include <time.h>

#include <stdio.h>



using namespace std;



const int CELL_SIZE = 16;

const int CELL_WIDTH = 16;

const int CELL_HEIGHT = 16;

const int SCREEN_WIDTH = CELL_SIZE * (CELL_WIDTH-1);

const int SCREEN_HEIGHT = CELL_SIZE * (CELL_HEIGHT-1);



SDL_Window* gWindow = NULL;

SDL_Renderer* gRenderer = NULL;



void loadTexture(string path);



SDL_Texture* spriteSheet = NULL;



void loadMedia();

void init();





class Snake {

    int initialLength = 3; //from body (head incluse)

    int length = initialLength;

    int facing = DIR_UP;



    //Head position in CELLS (multiplied for CELL_SIZE when drawed)

    int x = 5;

    int y = 5;



    //UNUSED TEMPORARY COLORS - IGNORE

    Uint8 color[3] = {0x22,0x88,0x44}; //Snake Color, em RGB

    Uint8 headColor[3] = {0x11,0x44,0x44}; //Color for the Head of the Snek



    int stepDelay = 60; //time in frames that the Snakes waits till move

    int stepFramesRemaining = stepDelay;

    int stepDelayReduction = 1; //reduces stepDelay every time the Snakes eats the apple

    const int minStepDelay = 15; //the minimum delay



    //For clipping the image (its an 16x16 png image)

    const SDL_Rect clipHead = {0,8,8,8};

    const SDL_Rect clipBody = {8,0,8,8};

    const SDL_Rect clipTail = {8,8,8,8};



    public:

        enum direction { //direções nas quais a cobra pode se mover

            DIR_UP,

            DIR_RIGHT,

            DIR_DOWN,

            DIR_LEFT

        };



        /* The following var stores the entire Snake's body in an 2D Array. The number stored means how much "steps" it will survive.

            When the value is zero, it means that there is no body in the place. The bodypart with value equivalent to "length" is the Head.

         */

        int body[CELL_WIDTH][CELL_HEIGHT];



        void init(); //initializes some vars

        void tick(); //tick function

        void stepFoward(); //moves Snake foward

        void faceTo(int dir); //alters which direction Snake is faced

        void eat(); //eats the apple

        void draw(); //renders (or at least tries) to render the snake



        int getLength(){

            return length;

        };



        int getFacing(){

            return facing;

        };

} Snake;



class Food {

    Uint8 color[3] = {0x85,0x22,0x10}; //RGB color of the Apple

    bool visible = true;



    public:

        int x = 2;

        int y = 2;



        void respawn();

        void destroy();

        void draw();

} Food;



void Food::respawn(){

    //teleports the apple to a random spot

    x = rand() % (CELL_WIDTH-2);

    y = rand() % (CELL_HEIGHT-2);

    visible = true;

}



void Food::destroy(){

    //Reset values

    x = 0;

    y = 0;

    visible = false;



    //resets

    respawn();

}



void Food::draw(){

    if(visible){

        SDL_Rect rect = {x*CELL_SIZE,y*CELL_SIZE,CELL_SIZE,CELL_SIZE};



        SDL_SetRenderDrawColor(gRenderer,color[0],color[1],color[2],0xff);

        SDL_RenderFillRect(gRenderer, &rect);

    }

}



void Snake::init(){

    //Spawns in a vertical line

    for(int i=0; i<length; i++){

        body[x][y+i] = length-i;

    }

}



void Snake::tick(){

    if(stepFramesRemaining > 0){

        stepFramesRemaining--;

    } else {

        //when 0, moves the snake

        stepFramesRemaining = stepDelay;



        stepFoward();

    }

}



void Snake::eat(){



    //increases the body size by 1

    for(int i=0; i<CELL_HEIGHT; i++){

        for(int j=0; j<CELL_WIDTH; j++){

            if(body[j][i] > 0){

                body[j][i]++;

            }

        }

    }

    length++;



    if(stepDelay > minStepDelay){

        stepDelay -= stepDelayReduction;

    }



    Food.destroy();

}



void Snake::draw(){

    //SDL_SetRenderDrawColor(gRenderer,color[0],color[1],color[2],0xff);

    SDL_Rect rect = {0,0,0,0}; //for later use



    //Draws the body and head

    for(int i=0; i<CELL_HEIGHT; i++){

        for(int j=0; j<CELL_WIDTH; j++){

            if(body[j][i] == length){

                rect = {j*CELL_SIZE,i*CELL_SIZE,CELL_SIZE,CELL_SIZE};



                SDL_SetRenderDrawColor(gRenderer,0x33,0xff,0x22,0xff);

                SDL_RenderFillRect(gRenderer,&rect);



                SDL_RenderCopy(gRenderer, spriteSheet, &clipHead, &rect);



            } else if (body[j][i] > 0){

                rect = {j*CELL_SIZE,i*CELL_SIZE,CELL_SIZE,CELL_SIZE};

                //SDL_SetRenderDrawColor(gRenderer,color[0],color[1],color[2],0xff);



                SDL_RenderCopyEx(gRenderer, spriteSheet, &clipBody, &rect, 0, NULL, SDL_FLIP_NONE);



                SDL_SetRenderDrawColor(gRenderer,0x66,0xee,0x22,0xff);

                SDL_RenderFillRect(gRenderer,&rect);

            }



            SDL_RenderFillRect(gRenderer,&rect);

        }

    }



    //SDL_RenderFillRect(gRenderer,&rect);

}



void Snake::stepFoward(){

    int headMoved = 0; //informs if the head already moved



    //decreases the "body" lifespan and moves head

    for(int i=0; i<CELL_HEIGHT; i++){

        for(int j=0; j<CELL_WIDTH; j++){

            if(body[j][i] > 0){

                //Verifica se é a cabeça, para movê-la logo em seguida

                if(body[j][i] == length && headMoved < 2){

                    //moves head position, looping if needed

                    switch(facing){

                    case DIR_UP:

                        if(y == 0){

                            body[x][CELL_HEIGHT-1] = length;

                            y = CELL_HEIGHT-1;

                        } else {

                            body[x][y-1] = length;

                            y--;

                        }

                        break;

                    case DIR_DOWN:

                        if(y == CELL_HEIGHT-2){

                            body[x][0] = length+1; //(+1 to avoid being subtracted twice)

                            y = 0;

                        } else {

                            body[x][y+1] = length+1;

                            y++;

                        }

                        break;

                    case DIR_LEFT:

                        if(x == 0){

                            body[CELL_WIDTH-1][y] = length;

                            x = CELL_WIDTH-1;

                        } else {

                            body[x-1][y] = length;

                            x--;

                        }

                        break;

                    case DIR_RIGHT:

                        if(x == CELL_WIDTH-2){

                            body[0][y] = length+1; //avoiding again the "-2" subtraction.

                            x = 0;

                        } else {

                            body[x+1][y] = length+1;

                            x++;

                        }

                        break;

                    }



                    headMoved++;

                }

                body[j][i]--; //decreases the "body" lifespan

            }

        }

    }



    //verifies if can eat (head in the same position as the apple)

    if(x == Food.x && y == Food.y){

        eat();

    }

}



void Snake::faceTo(int dir){

    facing = dir;

}



void init();



void close();



void init(){ //Initializes the game

    gWindow = SDL_CreateWindow("· Snake ·", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_SHOWN);

    gRenderer = SDL_CreateRenderer( gWindow, -1, SDL_RENDERER_ACCELERATED );

    if( gRenderer == NULL ){

        printf( "Renderer could not be created! SDL Error: %sn", SDL_GetError() );

    }



    int imgFlags = IMG_INIT_PNG;

    if(!(IMG_Init(imgFlags) & imgFlags)){

        cout << "IMG INIT error!" << endl;

    }



    loadMedia();

    Snake.init();

}



void close(){ //Closes the program

    SDL_DestroyTexture(spriteSheet);

    spriteSheet = NULL;

    SDL_DestroyRenderer(gRenderer);

    gRenderer = NULL;



    IMG_Quit();

    SDL_Quit();

}



void loadTexture(string path){ //Almost the same function from LazyFoo tutorial

    //The final texture

    SDL_Texture* newTexture = NULL;



    //Load image at specified path

    SDL_Surface* loadedSurface = IMG_Load( path.c_str() );

    if( loadedSurface == NULL )

    {

        printf( "Unable to load image %s! SDL_image Error: %sn", path.c_str(), IMG_GetError() );

    }

    else

    {

        //Color key image

        SDL_SetColorKey( loadedSurface, SDL_TRUE, SDL_MapRGB( loadedSurface->format, 0xff, 0x00, 0xff));



        //Create texture from surface pixels

        newTexture = SDL_CreateTextureFromSurface( gRenderer, loadedSurface);

        if( newTexture == NULL ){

            printf( "Unable to create texture from %s! SDL Error: %sn", path.c_str(), SDL_GetError() );

        }



        //Get rid of old loaded surface

        SDL_FreeSurface( loadedSurface );

    }



    spriteSheet = newTexture;

}



void loadMedia(){ //loads everything (it will load sound too, when i make the sounds of course)

    loadTexture("spritesheet.png");

    if(spriteSheet == NULL){

        cout << "ERRO" << endl;

    }

}



void tick(){ 

    Snake.tick();

}



void draw(){ //Render Function

    //Background

    SDL_SetRenderDrawColor(gRenderer, 0xee, 0xf2, 0xf0, 0xff);

    SDL_RenderClear(gRenderer);



    Snake.draw();

    Food.draw();



    //Aplica as alterações

    SDL_RenderPresent(gRenderer);

}



int main(){

    srand (time (NULL));

    init();



    bool quit = false;

    SDL_Event e; //Event Handling

    while(!quit){

        while(SDL_PollEvent(&e) != 0){

            if(e.type == SDL_QUIT){

                quit = true;

            } else if(e.type == SDL_KEYDOWN){

                switch(e.key.keysym.sym){

                case SDLK_UP:

                    Snake.faceTo(Snake.DIR_UP);

                    break;

                case SDLK_DOWN:

                    Snake.faceTo(Snake.DIR_DOWN);

                    break;

                case SDLK_LEFT:

                    Snake.faceTo(Snake.DIR_LEFT);

                    break;

                case SDLK_RIGHT:

                    Snake.faceTo(Snake.DIR_RIGHT);

                    break;

                }

            }

        }



        //Tick function

        tick();



        //Renders everything

        draw();



        SDL_RenderCopy(gRenderer, spriteSheet, NULL, NULL);



        //Slows down the program just a bit (its not a time based frame system... yet)

        SDL_Delay(3);

    }



    close(); //ends

    return 0;

}


The portion of code who should be working, but isn't:



//Draws the body and head

    for(int i=0; i<CELL_HEIGHT; i++){

        for(int j=0; j<CELL_WIDTH; j++){

            if(body[j][i] == length){

                rect = {j*CELL_SIZE,i*CELL_SIZE,CELL_SIZE,CELL_SIZE};



                SDL_SetRenderDrawColor(gRenderer,0x33,0xff,0x22,0xff);

                SDL_RenderFillRect(gRenderer,&rect);



                SDL_RenderCopy(gRenderer, spriteSheet, &clipHead, &rect);



            } else if (body[j][i] > 0){

                rect = {j*CELL_SIZE,i*CELL_SIZE,CELL_SIZE,CELL_SIZE};

                //SDL_SetRenderDrawColor(gRenderer,color[0],color[1],color[2],0xff);



                SDL_RenderCopyEx(gRenderer, spriteSheet, &clipBody, &rect, 0, NULL, SDL_FLIP_NONE);



                SDL_SetRenderDrawColor(gRenderer,0x66,0xee,0x22,0xff);

                SDL_RenderFillRect(gRenderer,&rect);

            }



            SDL_RenderFillRect(gRenderer,&rect);

        }

    }



    //SDL_RenderFillRect(gRenderer,&rect);

}





c++ textures sdl-2 renderer







share|improve this question


















  • 2





    In second if branch you RenderCopy and then immediately FillRect to the same rectangle, overwriting image result with fixed colour. And then doing that again outside of branch.

    – keltar
    Nov 28 '18 at 5:02











  • Thanks! It partially worked.

    – Bruno Peres
    Nov 29 '18 at 19:27
















1















I'm trying to make a simple Snake game. The self collision and a lot of things aren't ready. The problem is: Even with no errors, running just fine, changing "close()" to "endGame()" and reverting, rebuilding the entire program, i could not render anything with SDL_RenderCopy. You will see many unnecessary things in my code and some Brazilian-Portuguese comments, prepare yourself.



The image is a 16x16 png spritesheet, using the color #ff00ff as ColorKey. There are only 4 sprites in this spritesheet, respectively: Apple, Snake's Body, Snake's Head and Snake's Tail (still unused).



Whole code:



#include <iostream>

#include <SDL2/SDL.h>

#include <SDL2/SDL_image.h>

#include <stdlib.h>

#include <time.h>

#include <stdio.h>



using namespace std;



const int CELL_SIZE = 16;

const int CELL_WIDTH = 16;

const int CELL_HEIGHT = 16;

const int SCREEN_WIDTH = CELL_SIZE * (CELL_WIDTH-1);

const int SCREEN_HEIGHT = CELL_SIZE * (CELL_HEIGHT-1);



SDL_Window* gWindow = NULL;

SDL_Renderer* gRenderer = NULL;



void loadTexture(string path);



SDL_Texture* spriteSheet = NULL;



void loadMedia();

void init();





class Snake {

    int initialLength = 3; //from body (head incluse)

    int length = initialLength;

    int facing = DIR_UP;



    //Head position in CELLS (multiplied for CELL_SIZE when drawed)

    int x = 5;

    int y = 5;



    //UNUSED TEMPORARY COLORS - IGNORE

    Uint8 color[3] = {0x22,0x88,0x44}; //Snake Color, em RGB

    Uint8 headColor[3] = {0x11,0x44,0x44}; //Color for the Head of the Snek



    int stepDelay = 60; //time in frames that the Snakes waits till move

    int stepFramesRemaining = stepDelay;

    int stepDelayReduction = 1; //reduces stepDelay every time the Snakes eats the apple

    const int minStepDelay = 15; //the minimum delay



    //For clipping the image (its an 16x16 png image)

    const SDL_Rect clipHead = {0,8,8,8};

    const SDL_Rect clipBody = {8,0,8,8};

    const SDL_Rect clipTail = {8,8,8,8};



    public:

        enum direction { //direções nas quais a cobra pode se mover

            DIR_UP,

            DIR_RIGHT,

            DIR_DOWN,

            DIR_LEFT

        };



        /* The following var stores the entire Snake's body in an 2D Array. The number stored means how much "steps" it will survive.

            When the value is zero, it means that there is no body in the place. The bodypart with value equivalent to "length" is the Head.

         */

        int body[CELL_WIDTH][CELL_HEIGHT];



        void init(); //initializes some vars

        void tick(); //tick function

        void stepFoward(); //moves Snake foward

        void faceTo(int dir); //alters which direction Snake is faced

        void eat(); //eats the apple

        void draw(); //renders (or at least tries) to render the snake



        int getLength(){

            return length;

        };



        int getFacing(){

            return facing;

        };

} Snake;



class Food {

    Uint8 color[3] = {0x85,0x22,0x10}; //RGB color of the Apple

    bool visible = true;



    public:

        int x = 2;

        int y = 2;



        void respawn();

        void destroy();

        void draw();

} Food;



void Food::respawn(){

    //teleports the apple to a random spot

    x = rand() % (CELL_WIDTH-2);

    y = rand() % (CELL_HEIGHT-2);

    visible = true;

}



void Food::destroy(){

    //Reset values

    x = 0;

    y = 0;

    visible = false;



    //resets

    respawn();

}



void Food::draw(){

    if(visible){

        SDL_Rect rect = {x*CELL_SIZE,y*CELL_SIZE,CELL_SIZE,CELL_SIZE};



        SDL_SetRenderDrawColor(gRenderer,color[0],color[1],color[2],0xff);

        SDL_RenderFillRect(gRenderer, &rect);

    }

}



void Snake::init(){

    //Spawns in a vertical line

    for(int i=0; i<length; i++){

        body[x][y+i] = length-i;

    }

}



void Snake::tick(){

    if(stepFramesRemaining > 0){

        stepFramesRemaining--;

    } else {

        //when 0, moves the snake

        stepFramesRemaining = stepDelay;



        stepFoward();

    }

}



void Snake::eat(){



    //increases the body size by 1

    for(int i=0; i<CELL_HEIGHT; i++){

        for(int j=0; j<CELL_WIDTH; j++){

            if(body[j][i] > 0){

                body[j][i]++;

            }

        }

    }

    length++;



    if(stepDelay > minStepDelay){

        stepDelay -= stepDelayReduction;

    }



    Food.destroy();

}



void Snake::draw(){

    //SDL_SetRenderDrawColor(gRenderer,color[0],color[1],color[2],0xff);

    SDL_Rect rect = {0,0,0,0}; //for later use



    //Draws the body and head

    for(int i=0; i<CELL_HEIGHT; i++){

        for(int j=0; j<CELL_WIDTH; j++){

            if(body[j][i] == length){

                rect = {j*CELL_SIZE,i*CELL_SIZE,CELL_SIZE,CELL_SIZE};



                SDL_SetRenderDrawColor(gRenderer,0x33,0xff,0x22,0xff);

                SDL_RenderFillRect(gRenderer,&rect);



                SDL_RenderCopy(gRenderer, spriteSheet, &clipHead, &rect);



            } else if (body[j][i] > 0){

                rect = {j*CELL_SIZE,i*CELL_SIZE,CELL_SIZE,CELL_SIZE};

                //SDL_SetRenderDrawColor(gRenderer,color[0],color[1],color[2],0xff);



                SDL_RenderCopyEx(gRenderer, spriteSheet, &clipBody, &rect, 0, NULL, SDL_FLIP_NONE);



                SDL_SetRenderDrawColor(gRenderer,0x66,0xee,0x22,0xff);

                SDL_RenderFillRect(gRenderer,&rect);

            }



            SDL_RenderFillRect(gRenderer,&rect);

        }

    }



    //SDL_RenderFillRect(gRenderer,&rect);

}



void Snake::stepFoward(){

    int headMoved = 0; //informs if the head already moved



    //decreases the "body" lifespan and moves head

    for(int i=0; i<CELL_HEIGHT; i++){

        for(int j=0; j<CELL_WIDTH; j++){

            if(body[j][i] > 0){

                //Verifica se é a cabeça, para movê-la logo em seguida

                if(body[j][i] == length && headMoved < 2){

                    //moves head position, looping if needed

                    switch(facing){

                    case DIR_UP:

                        if(y == 0){

                            body[x][CELL_HEIGHT-1] = length;

                            y = CELL_HEIGHT-1;

                        } else {

                            body[x][y-1] = length;

                            y--;

                        }

                        break;

                    case DIR_DOWN:

                        if(y == CELL_HEIGHT-2){

                            body[x][0] = length+1; //(+1 to avoid being subtracted twice)

                            y = 0;

                        } else {

                            body[x][y+1] = length+1;

                            y++;

                        }

                        break;

                    case DIR_LEFT:

                        if(x == 0){

                            body[CELL_WIDTH-1][y] = length;

                            x = CELL_WIDTH-1;

                        } else {

                            body[x-1][y] = length;

                            x--;

                        }

                        break;

                    case DIR_RIGHT:

                        if(x == CELL_WIDTH-2){

                            body[0][y] = length+1; //avoiding again the "-2" subtraction.

                            x = 0;

                        } else {

                            body[x+1][y] = length+1;

                            x++;

                        }

                        break;

                    }



                    headMoved++;

                }

                body[j][i]--; //decreases the "body" lifespan

            }

        }

    }



    //verifies if can eat (head in the same position as the apple)

    if(x == Food.x && y == Food.y){

        eat();

    }

}



void Snake::faceTo(int dir){

    facing = dir;

}



void init();



void close();



void init(){ //Initializes the game

    gWindow = SDL_CreateWindow("· Snake ·", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_SHOWN);

    gRenderer = SDL_CreateRenderer( gWindow, -1, SDL_RENDERER_ACCELERATED );

    if( gRenderer == NULL ){

        printf( "Renderer could not be created! SDL Error: %sn", SDL_GetError() );

    }



    int imgFlags = IMG_INIT_PNG;

    if(!(IMG_Init(imgFlags) & imgFlags)){

        cout << "IMG INIT error!" << endl;

    }



    loadMedia();

    Snake.init();

}



void close(){ //Closes the program

    SDL_DestroyTexture(spriteSheet);

    spriteSheet = NULL;

    SDL_DestroyRenderer(gRenderer);

    gRenderer = NULL;



    IMG_Quit();

    SDL_Quit();

}



void loadTexture(string path){ //Almost the same function from LazyFoo tutorial

    //The final texture

    SDL_Texture* newTexture = NULL;



    //Load image at specified path

    SDL_Surface* loadedSurface = IMG_Load( path.c_str() );

    if( loadedSurface == NULL )

    {

        printf( "Unable to load image %s! SDL_image Error: %sn", path.c_str(), IMG_GetError() );

    }

    else

    {

        //Color key image

        SDL_SetColorKey( loadedSurface, SDL_TRUE, SDL_MapRGB( loadedSurface->format, 0xff, 0x00, 0xff));



        //Create texture from surface pixels

        newTexture = SDL_CreateTextureFromSurface( gRenderer, loadedSurface);

        if( newTexture == NULL ){

            printf( "Unable to create texture from %s! SDL Error: %sn", path.c_str(), SDL_GetError() );

        }



        //Get rid of old loaded surface

        SDL_FreeSurface( loadedSurface );

    }



    spriteSheet = newTexture;

}



void loadMedia(){ //loads everything (it will load sound too, when i make the sounds of course)

    loadTexture("spritesheet.png");

    if(spriteSheet == NULL){

        cout << "ERRO" << endl;

    }

}



void tick(){ 

    Snake.tick();

}



void draw(){ //Render Function

    //Background

    SDL_SetRenderDrawColor(gRenderer, 0xee, 0xf2, 0xf0, 0xff);

    SDL_RenderClear(gRenderer);



    Snake.draw();

    Food.draw();



    //Aplica as alterações

    SDL_RenderPresent(gRenderer);

}



int main(){

    srand (time (NULL));

    init();



    bool quit = false;

    SDL_Event e; //Event Handling

    while(!quit){

        while(SDL_PollEvent(&e) != 0){

            if(e.type == SDL_QUIT){

                quit = true;

            } else if(e.type == SDL_KEYDOWN){

                switch(e.key.keysym.sym){

                case SDLK_UP:

                    Snake.faceTo(Snake.DIR_UP);

                    break;

                case SDLK_DOWN:

                    Snake.faceTo(Snake.DIR_DOWN);

                    break;

                case SDLK_LEFT:

                    Snake.faceTo(Snake.DIR_LEFT);

                    break;

                case SDLK_RIGHT:

                    Snake.faceTo(Snake.DIR_RIGHT);

                    break;

                }

            }

        }



        //Tick function

        tick();



        //Renders everything

        draw();



        SDL_RenderCopy(gRenderer, spriteSheet, NULL, NULL);



        //Slows down the program just a bit (its not a time based frame system... yet)

        SDL_Delay(3);

    }



    close(); //ends

    return 0;

}


The portion of code who should be working, but isn't:



//Draws the body and head

    for(int i=0; i<CELL_HEIGHT; i++){

        for(int j=0; j<CELL_WIDTH; j++){

            if(body[j][i] == length){

                rect = {j*CELL_SIZE,i*CELL_SIZE,CELL_SIZE,CELL_SIZE};



                SDL_SetRenderDrawColor(gRenderer,0x33,0xff,0x22,0xff);

                SDL_RenderFillRect(gRenderer,&rect);



                SDL_RenderCopy(gRenderer, spriteSheet, &clipHead, &rect);



            } else if (body[j][i] > 0){

                rect = {j*CELL_SIZE,i*CELL_SIZE,CELL_SIZE,CELL_SIZE};

                //SDL_SetRenderDrawColor(gRenderer,color[0],color[1],color[2],0xff);



                SDL_RenderCopyEx(gRenderer, spriteSheet, &clipBody, &rect, 0, NULL, SDL_FLIP_NONE);



                SDL_SetRenderDrawColor(gRenderer,0x66,0xee,0x22,0xff);

                SDL_RenderFillRect(gRenderer,&rect);

            }



            SDL_RenderFillRect(gRenderer,&rect);

        }

    }



    //SDL_RenderFillRect(gRenderer,&rect);

}





c++ textures sdl-2 renderer







share|improve this question


















  • 2





    In second if branch you RenderCopy and then immediately FillRect to the same rectangle, overwriting image result with fixed colour. And then doing that again outside of branch.

    – keltar
    Nov 28 '18 at 5:02











  • Thanks! It partially worked.

    – Bruno Peres
    Nov 29 '18 at 19:27














1












1








1








I'm trying to make a simple Snake game. The self collision and a lot of things aren't ready. The problem is: Even with no errors, running just fine, changing "close()" to "endGame()" and reverting, rebuilding the entire program, i could not render anything with SDL_RenderCopy. You will see many unnecessary things in my code and some Brazilian-Portuguese comments, prepare yourself.



The image is a 16x16 png spritesheet, using the color #ff00ff as ColorKey. There are only 4 sprites in this spritesheet, respectively: Apple, Snake's Body, Snake's Head and Snake's Tail (still unused).



Whole code:



#include <iostream>

#include <SDL2/SDL.h>

#include <SDL2/SDL_image.h>

#include <stdlib.h>

#include <time.h>

#include <stdio.h>



using namespace std;



const int CELL_SIZE = 16;

const int CELL_WIDTH = 16;

const int CELL_HEIGHT = 16;

const int SCREEN_WIDTH = CELL_SIZE * (CELL_WIDTH-1);

const int SCREEN_HEIGHT = CELL_SIZE * (CELL_HEIGHT-1);



SDL_Window* gWindow = NULL;

SDL_Renderer* gRenderer = NULL;



void loadTexture(string path);



SDL_Texture* spriteSheet = NULL;



void loadMedia();

void init();





class Snake {

    int initialLength = 3; //from body (head incluse)

    int length = initialLength;

    int facing = DIR_UP;



    //Head position in CELLS (multiplied for CELL_SIZE when drawed)

    int x = 5;

    int y = 5;



    //UNUSED TEMPORARY COLORS - IGNORE

    Uint8 color[3] = {0x22,0x88,0x44}; //Snake Color, em RGB

    Uint8 headColor[3] = {0x11,0x44,0x44}; //Color for the Head of the Snek



    int stepDelay = 60; //time in frames that the Snakes waits till move

    int stepFramesRemaining = stepDelay;

    int stepDelayReduction = 1; //reduces stepDelay every time the Snakes eats the apple

    const int minStepDelay = 15; //the minimum delay



    //For clipping the image (its an 16x16 png image)

    const SDL_Rect clipHead = {0,8,8,8};

    const SDL_Rect clipBody = {8,0,8,8};

    const SDL_Rect clipTail = {8,8,8,8};



    public:

        enum direction { //direções nas quais a cobra pode se mover

            DIR_UP,

            DIR_RIGHT,

            DIR_DOWN,

            DIR_LEFT

        };



        /* The following var stores the entire Snake's body in an 2D Array. The number stored means how much "steps" it will survive.

            When the value is zero, it means that there is no body in the place. The bodypart with value equivalent to "length" is the Head.

         */

        int body[CELL_WIDTH][CELL_HEIGHT];



        void init(); //initializes some vars

        void tick(); //tick function

        void stepFoward(); //moves Snake foward

        void faceTo(int dir); //alters which direction Snake is faced

        void eat(); //eats the apple

        void draw(); //renders (or at least tries) to render the snake



        int getLength(){

            return length;

        };



        int getFacing(){

            return facing;

        };

} Snake;



class Food {

    Uint8 color[3] = {0x85,0x22,0x10}; //RGB color of the Apple

    bool visible = true;



    public:

        int x = 2;

        int y = 2;



        void respawn();

        void destroy();

        void draw();

} Food;



void Food::respawn(){

    //teleports the apple to a random spot

    x = rand() % (CELL_WIDTH-2);

    y = rand() % (CELL_HEIGHT-2);

    visible = true;

}



void Food::destroy(){

    //Reset values

    x = 0;

    y = 0;

    visible = false;



    //resets

    respawn();

}



void Food::draw(){

    if(visible){

        SDL_Rect rect = {x*CELL_SIZE,y*CELL_SIZE,CELL_SIZE,CELL_SIZE};



        SDL_SetRenderDrawColor(gRenderer,color[0],color[1],color[2],0xff);

        SDL_RenderFillRect(gRenderer, &rect);

    }

}



void Snake::init(){

    //Spawns in a vertical line

    for(int i=0; i<length; i++){

        body[x][y+i] = length-i;

    }

}



void Snake::tick(){

    if(stepFramesRemaining > 0){

        stepFramesRemaining--;

    } else {

        //when 0, moves the snake

        stepFramesRemaining = stepDelay;



        stepFoward();

    }

}



void Snake::eat(){



    //increases the body size by 1

    for(int i=0; i<CELL_HEIGHT; i++){

        for(int j=0; j<CELL_WIDTH; j++){

            if(body[j][i] > 0){

                body[j][i]++;

            }

        }

    }

    length++;



    if(stepDelay > minStepDelay){

        stepDelay -= stepDelayReduction;

    }



    Food.destroy();

}



void Snake::draw(){

    //SDL_SetRenderDrawColor(gRenderer,color[0],color[1],color[2],0xff);

    SDL_Rect rect = {0,0,0,0}; //for later use



    //Draws the body and head

    for(int i=0; i<CELL_HEIGHT; i++){

        for(int j=0; j<CELL_WIDTH; j++){

            if(body[j][i] == length){

                rect = {j*CELL_SIZE,i*CELL_SIZE,CELL_SIZE,CELL_SIZE};



                SDL_SetRenderDrawColor(gRenderer,0x33,0xff,0x22,0xff);

                SDL_RenderFillRect(gRenderer,&rect);



                SDL_RenderCopy(gRenderer, spriteSheet, &clipHead, &rect);



            } else if (body[j][i] > 0){

                rect = {j*CELL_SIZE,i*CELL_SIZE,CELL_SIZE,CELL_SIZE};

                //SDL_SetRenderDrawColor(gRenderer,color[0],color[1],color[2],0xff);



                SDL_RenderCopyEx(gRenderer, spriteSheet, &clipBody, &rect, 0, NULL, SDL_FLIP_NONE);



                SDL_SetRenderDrawColor(gRenderer,0x66,0xee,0x22,0xff);

                SDL_RenderFillRect(gRenderer,&rect);

            }



            SDL_RenderFillRect(gRenderer,&rect);

        }

    }



    //SDL_RenderFillRect(gRenderer,&rect);

}



void Snake::stepFoward(){

    int headMoved = 0; //informs if the head already moved



    //decreases the "body" lifespan and moves head

    for(int i=0; i<CELL_HEIGHT; i++){

        for(int j=0; j<CELL_WIDTH; j++){

            if(body[j][i] > 0){

                //Verifica se é a cabeça, para movê-la logo em seguida

                if(body[j][i] == length && headMoved < 2){

                    //moves head position, looping if needed

                    switch(facing){

                    case DIR_UP:

                        if(y == 0){

                            body[x][CELL_HEIGHT-1] = length;

                            y = CELL_HEIGHT-1;

                        } else {

                            body[x][y-1] = length;

                            y--;

                        }

                        break;

                    case DIR_DOWN:

                        if(y == CELL_HEIGHT-2){

                            body[x][0] = length+1; //(+1 to avoid being subtracted twice)

                            y = 0;

                        } else {

                            body[x][y+1] = length+1;

                            y++;

                        }

                        break;

                    case DIR_LEFT:

                        if(x == 0){

                            body[CELL_WIDTH-1][y] = length;

                            x = CELL_WIDTH-1;

                        } else {

                            body[x-1][y] = length;

                            x--;

                        }

                        break;

                    case DIR_RIGHT:

                        if(x == CELL_WIDTH-2){

                            body[0][y] = length+1; //avoiding again the "-2" subtraction.

                            x = 0;

                        } else {

                            body[x+1][y] = length+1;

                            x++;

                        }

                        break;

                    }



                    headMoved++;

                }

                body[j][i]--; //decreases the "body" lifespan

            }

        }

    }



    //verifies if can eat (head in the same position as the apple)

    if(x == Food.x && y == Food.y){

        eat();

    }

}



void Snake::faceTo(int dir){

    facing = dir;

}



void init();



void close();



void init(){ //Initializes the game

    gWindow = SDL_CreateWindow("· Snake ·", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_SHOWN);

    gRenderer = SDL_CreateRenderer( gWindow, -1, SDL_RENDERER_ACCELERATED );

    if( gRenderer == NULL ){

        printf( "Renderer could not be created! SDL Error: %sn", SDL_GetError() );

    }



    int imgFlags = IMG_INIT_PNG;

    if(!(IMG_Init(imgFlags) & imgFlags)){

        cout << "IMG INIT error!" << endl;

    }



    loadMedia();

    Snake.init();

}



void close(){ //Closes the program

    SDL_DestroyTexture(spriteSheet);

    spriteSheet = NULL;

    SDL_DestroyRenderer(gRenderer);

    gRenderer = NULL;



    IMG_Quit();

    SDL_Quit();

}



void loadTexture(string path){ //Almost the same function from LazyFoo tutorial

    //The final texture

    SDL_Texture* newTexture = NULL;



    //Load image at specified path

    SDL_Surface* loadedSurface = IMG_Load( path.c_str() );

    if( loadedSurface == NULL )

    {

        printf( "Unable to load image %s! SDL_image Error: %sn", path.c_str(), IMG_GetError() );

    }

    else

    {

        //Color key image

        SDL_SetColorKey( loadedSurface, SDL_TRUE, SDL_MapRGB( loadedSurface->format, 0xff, 0x00, 0xff));



        //Create texture from surface pixels

        newTexture = SDL_CreateTextureFromSurface( gRenderer, loadedSurface);

        if( newTexture == NULL ){

            printf( "Unable to create texture from %s! SDL Error: %sn", path.c_str(), SDL_GetError() );

        }



        //Get rid of old loaded surface

        SDL_FreeSurface( loadedSurface );

    }



    spriteSheet = newTexture;

}



void loadMedia(){ //loads everything (it will load sound too, when i make the sounds of course)

    loadTexture("spritesheet.png");

    if(spriteSheet == NULL){

        cout << "ERRO" << endl;

    }

}



void tick(){ 

    Snake.tick();

}



void draw(){ //Render Function

    //Background

    SDL_SetRenderDrawColor(gRenderer, 0xee, 0xf2, 0xf0, 0xff);

    SDL_RenderClear(gRenderer);



    Snake.draw();

    Food.draw();



    //Aplica as alterações

    SDL_RenderPresent(gRenderer);

}



int main(){

    srand (time (NULL));

    init();



    bool quit = false;

    SDL_Event e; //Event Handling

    while(!quit){

        while(SDL_PollEvent(&e) != 0){

            if(e.type == SDL_QUIT){

                quit = true;

            } else if(e.type == SDL_KEYDOWN){

                switch(e.key.keysym.sym){

                case SDLK_UP:

                    Snake.faceTo(Snake.DIR_UP);

                    break;

                case SDLK_DOWN:

                    Snake.faceTo(Snake.DIR_DOWN);

                    break;

                case SDLK_LEFT:

                    Snake.faceTo(Snake.DIR_LEFT);

                    break;

                case SDLK_RIGHT:

                    Snake.faceTo(Snake.DIR_RIGHT);

                    break;

                }

            }

        }



        //Tick function

        tick();



        //Renders everything

        draw();



        SDL_RenderCopy(gRenderer, spriteSheet, NULL, NULL);



        //Slows down the program just a bit (its not a time based frame system... yet)

        SDL_Delay(3);

    }



    close(); //ends

    return 0;

}


The portion of code who should be working, but isn't:



//Draws the body and head

    for(int i=0; i<CELL_HEIGHT; i++){

        for(int j=0; j<CELL_WIDTH; j++){

            if(body[j][i] == length){

                rect = {j*CELL_SIZE,i*CELL_SIZE,CELL_SIZE,CELL_SIZE};



                SDL_SetRenderDrawColor(gRenderer,0x33,0xff,0x22,0xff);

                SDL_RenderFillRect(gRenderer,&rect);



                SDL_RenderCopy(gRenderer, spriteSheet, &clipHead, &rect);



            } else if (body[j][i] > 0){

                rect = {j*CELL_SIZE,i*CELL_SIZE,CELL_SIZE,CELL_SIZE};

                //SDL_SetRenderDrawColor(gRenderer,color[0],color[1],color[2],0xff);



                SDL_RenderCopyEx(gRenderer, spriteSheet, &clipBody, &rect, 0, NULL, SDL_FLIP_NONE);



                SDL_SetRenderDrawColor(gRenderer,0x66,0xee,0x22,0xff);

                SDL_RenderFillRect(gRenderer,&rect);

            }



            SDL_RenderFillRect(gRenderer,&rect);

        }

    }



    //SDL_RenderFillRect(gRenderer,&rect);

}





c++ textures sdl-2 renderer







share|improve this question














I'm trying to make a simple Snake game. The self collision and a lot of things aren't ready. The problem is: Even with no errors, running just fine, changing "close()" to "endGame()" and reverting, rebuilding the entire program, i could not render anything with SDL_RenderCopy. You will see many unnecessary things in my code and some Brazilian-Portuguese comments, prepare yourself.



The image is a 16x16 png spritesheet, using the color #ff00ff as ColorKey. There are only 4 sprites in this spritesheet, respectively: Apple, Snake's Body, Snake's Head and Snake's Tail (still unused).



Whole code:



#include <iostream>

#include <SDL2/SDL.h>

#include <SDL2/SDL_image.h>

#include <stdlib.h>

#include <time.h>

#include <stdio.h>



using namespace std;



const int CELL_SIZE = 16;

const int CELL_WIDTH = 16;

const int CELL_HEIGHT = 16;

const int SCREEN_WIDTH = CELL_SIZE * (CELL_WIDTH-1);

const int SCREEN_HEIGHT = CELL_SIZE * (CELL_HEIGHT-1);



SDL_Window* gWindow = NULL;

SDL_Renderer* gRenderer = NULL;



void loadTexture(string path);



SDL_Texture* spriteSheet = NULL;



void loadMedia();

void init();





class Snake {

    int initialLength = 3; //from body (head incluse)

    int length = initialLength;

    int facing = DIR_UP;



    //Head position in CELLS (multiplied for CELL_SIZE when drawed)

    int x = 5;

    int y = 5;



    //UNUSED TEMPORARY COLORS - IGNORE

    Uint8 color[3] = {0x22,0x88,0x44}; //Snake Color, em RGB

    Uint8 headColor[3] = {0x11,0x44,0x44}; //Color for the Head of the Snek



    int stepDelay = 60; //time in frames that the Snakes waits till move

    int stepFramesRemaining = stepDelay;

    int stepDelayReduction = 1; //reduces stepDelay every time the Snakes eats the apple

    const int minStepDelay = 15; //the minimum delay



    //For clipping the image (its an 16x16 png image)

    const SDL_Rect clipHead = {0,8,8,8};

    const SDL_Rect clipBody = {8,0,8,8};

    const SDL_Rect clipTail = {8,8,8,8};



    public:

        enum direction { //direções nas quais a cobra pode se mover

            DIR_UP,

            DIR_RIGHT,

            DIR_DOWN,

            DIR_LEFT

        };



        /* The following var stores the entire Snake's body in an 2D Array. The number stored means how much "steps" it will survive.

            When the value is zero, it means that there is no body in the place. The bodypart with value equivalent to "length" is the Head.

         */

        int body[CELL_WIDTH][CELL_HEIGHT];



        void init(); //initializes some vars

        void tick(); //tick function

        void stepFoward(); //moves Snake foward

        void faceTo(int dir); //alters which direction Snake is faced

        void eat(); //eats the apple

        void draw(); //renders (or at least tries) to render the snake



        int getLength(){

            return length;

        };



        int getFacing(){

            return facing;

        };

} Snake;



class Food {

    Uint8 color[3] = {0x85,0x22,0x10}; //RGB color of the Apple

    bool visible = true;



    public:

        int x = 2;

        int y = 2;



        void respawn();

        void destroy();

        void draw();

} Food;



void Food::respawn(){

    //teleports the apple to a random spot

    x = rand() % (CELL_WIDTH-2);

    y = rand() % (CELL_HEIGHT-2);

    visible = true;

}



void Food::destroy(){

    //Reset values

    x = 0;

    y = 0;

    visible = false;



    //resets

    respawn();

}



void Food::draw(){

    if(visible){

        SDL_Rect rect = {x*CELL_SIZE,y*CELL_SIZE,CELL_SIZE,CELL_SIZE};



        SDL_SetRenderDrawColor(gRenderer,color[0],color[1],color[2],0xff);

        SDL_RenderFillRect(gRenderer, &rect);

    }

}



void Snake::init(){

    //Spawns in a vertical line

    for(int i=0; i<length; i++){

        body[x][y+i] = length-i;

    }

}



void Snake::tick(){

    if(stepFramesRemaining > 0){

        stepFramesRemaining--;

    } else {

        //when 0, moves the snake

        stepFramesRemaining = stepDelay;



        stepFoward();

    }

}



void Snake::eat(){



    //increases the body size by 1

    for(int i=0; i<CELL_HEIGHT; i++){

        for(int j=0; j<CELL_WIDTH; j++){

            if(body[j][i] > 0){

                body[j][i]++;

            }

        }

    }

    length++;



    if(stepDelay > minStepDelay){

        stepDelay -= stepDelayReduction;

    }



    Food.destroy();

}



void Snake::draw(){

    //SDL_SetRenderDrawColor(gRenderer,color[0],color[1],color[2],0xff);

    SDL_Rect rect = {0,0,0,0}; //for later use



    //Draws the body and head

    for(int i=0; i<CELL_HEIGHT; i++){

        for(int j=0; j<CELL_WIDTH; j++){

            if(body[j][i] == length){

                rect = {j*CELL_SIZE,i*CELL_SIZE,CELL_SIZE,CELL_SIZE};



                SDL_SetRenderDrawColor(gRenderer,0x33,0xff,0x22,0xff);

                SDL_RenderFillRect(gRenderer,&rect);



                SDL_RenderCopy(gRenderer, spriteSheet, &clipHead, &rect);



            } else if (body[j][i] > 0){

                rect = {j*CELL_SIZE,i*CELL_SIZE,CELL_SIZE,CELL_SIZE};

                //SDL_SetRenderDrawColor(gRenderer,color[0],color[1],color[2],0xff);



                SDL_RenderCopyEx(gRenderer, spriteSheet, &clipBody, &rect, 0, NULL, SDL_FLIP_NONE);



                SDL_SetRenderDrawColor(gRenderer,0x66,0xee,0x22,0xff);

                SDL_RenderFillRect(gRenderer,&rect);

            }



            SDL_RenderFillRect(gRenderer,&rect);

        }

    }



    //SDL_RenderFillRect(gRenderer,&rect);

}



void Snake::stepFoward(){

    int headMoved = 0; //informs if the head already moved



    //decreases the "body" lifespan and moves head

    for(int i=0; i<CELL_HEIGHT; i++){

        for(int j=0; j<CELL_WIDTH; j++){

            if(body[j][i] > 0){

                //Verifica se é a cabeça, para movê-la logo em seguida

                if(body[j][i] == length && headMoved < 2){

                    //moves head position, looping if needed

                    switch(facing){

                    case DIR_UP:

                        if(y == 0){

                            body[x][CELL_HEIGHT-1] = length;

                            y = CELL_HEIGHT-1;

                        } else {

                            body[x][y-1] = length;

                            y--;

                        }

                        break;

                    case DIR_DOWN:

                        if(y == CELL_HEIGHT-2){

                            body[x][0] = length+1; //(+1 to avoid being subtracted twice)

                            y = 0;

                        } else {

                            body[x][y+1] = length+1;

                            y++;

                        }

                        break;

                    case DIR_LEFT:

                        if(x == 0){

                            body[CELL_WIDTH-1][y] = length;

                            x = CELL_WIDTH-1;

                        } else {

                            body[x-1][y] = length;

                            x--;

                        }

                        break;

                    case DIR_RIGHT:

                        if(x == CELL_WIDTH-2){

                            body[0][y] = length+1; //avoiding again the "-2" subtraction.

                            x = 0;

                        } else {

                            body[x+1][y] = length+1;

                            x++;

                        }

                        break;

                    }



                    headMoved++;

                }

                body[j][i]--; //decreases the "body" lifespan

            }

        }

    }



    //verifies if can eat (head in the same position as the apple)

    if(x == Food.x && y == Food.y){

        eat();

    }

}



void Snake::faceTo(int dir){

    facing = dir;

}



void init();



void close();



void init(){ //Initializes the game

    gWindow = SDL_CreateWindow("· Snake ·", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_SHOWN);

    gRenderer = SDL_CreateRenderer( gWindow, -1, SDL_RENDERER_ACCELERATED );

    if( gRenderer == NULL ){

        printf( "Renderer could not be created! SDL Error: %sn", SDL_GetError() );

    }



    int imgFlags = IMG_INIT_PNG;

    if(!(IMG_Init(imgFlags) & imgFlags)){

        cout << "IMG INIT error!" << endl;

    }



    loadMedia();

    Snake.init();

}



void close(){ //Closes the program

    SDL_DestroyTexture(spriteSheet);

    spriteSheet = NULL;

    SDL_DestroyRenderer(gRenderer);

    gRenderer = NULL;



    IMG_Quit();

    SDL_Quit();

}



void loadTexture(string path){ //Almost the same function from LazyFoo tutorial

    //The final texture

    SDL_Texture* newTexture = NULL;



    //Load image at specified path

    SDL_Surface* loadedSurface = IMG_Load( path.c_str() );

    if( loadedSurface == NULL )

    {

        printf( "Unable to load image %s! SDL_image Error: %sn", path.c_str(), IMG_GetError() );

    }

    else

    {

        //Color key image

        SDL_SetColorKey( loadedSurface, SDL_TRUE, SDL_MapRGB( loadedSurface->format, 0xff, 0x00, 0xff));



        //Create texture from surface pixels

        newTexture = SDL_CreateTextureFromSurface( gRenderer, loadedSurface);

        if( newTexture == NULL ){

            printf( "Unable to create texture from %s! SDL Error: %sn", path.c_str(), SDL_GetError() );

        }



        //Get rid of old loaded surface

        SDL_FreeSurface( loadedSurface );

    }



    spriteSheet = newTexture;

}



void loadMedia(){ //loads everything (it will load sound too, when i make the sounds of course)

    loadTexture("spritesheet.png");

    if(spriteSheet == NULL){

        cout << "ERRO" << endl;

    }

}



void tick(){ 

    Snake.tick();

}



void draw(){ //Render Function

    //Background

    SDL_SetRenderDrawColor(gRenderer, 0xee, 0xf2, 0xf0, 0xff);

    SDL_RenderClear(gRenderer);



    Snake.draw();

    Food.draw();



    //Aplica as alterações

    SDL_RenderPresent(gRenderer);

}



int main(){

    srand (time (NULL));

    init();



    bool quit = false;

    SDL_Event e; //Event Handling

    while(!quit){

        while(SDL_PollEvent(&e) != 0){

            if(e.type == SDL_QUIT){

                quit = true;

            } else if(e.type == SDL_KEYDOWN){

                switch(e.key.keysym.sym){

                case SDLK_UP:

                    Snake.faceTo(Snake.DIR_UP);

                    break;

                case SDLK_DOWN:

                    Snake.faceTo(Snake.DIR_DOWN);

                    break;

                case SDLK_LEFT:

                    Snake.faceTo(Snake.DIR_LEFT);

                    break;

                case SDLK_RIGHT:

                    Snake.faceTo(Snake.DIR_RIGHT);

                    break;

                }

            }

        }



        //Tick function

        tick();



        //Renders everything

        draw();



        SDL_RenderCopy(gRenderer, spriteSheet, NULL, NULL);



        //Slows down the program just a bit (its not a time based frame system... yet)

        SDL_Delay(3);

    }



    close(); //ends

    return 0;

}


The portion of code who should be working, but isn't:



//Draws the body and head

    for(int i=0; i<CELL_HEIGHT; i++){

        for(int j=0; j<CELL_WIDTH; j++){

            if(body[j][i] == length){

                rect = {j*CELL_SIZE,i*CELL_SIZE,CELL_SIZE,CELL_SIZE};



                SDL_SetRenderDrawColor(gRenderer,0x33,0xff,0x22,0xff);

                SDL_RenderFillRect(gRenderer,&rect);



                SDL_RenderCopy(gRenderer, spriteSheet, &clipHead, &rect);



            } else if (body[j][i] > 0){

                rect = {j*CELL_SIZE,i*CELL_SIZE,CELL_SIZE,CELL_SIZE};

                //SDL_SetRenderDrawColor(gRenderer,color[0],color[1],color[2],0xff);



                SDL_RenderCopyEx(gRenderer, spriteSheet, &clipBody, &rect, 0, NULL, SDL_FLIP_NONE);



                SDL_SetRenderDrawColor(gRenderer,0x66,0xee,0x22,0xff);

                SDL_RenderFillRect(gRenderer,&rect);

            }



            SDL_RenderFillRect(gRenderer,&rect);

        }

    }



    //SDL_RenderFillRect(gRenderer,&rect);

}





c++ textures sdl-2 renderer




c++ textures sdl-2 renderer






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked Nov 28 '18 at 2:29









Bruno PeresBruno Peres

61




61








  • 2





    In second if branch you RenderCopy and then immediately FillRect to the same rectangle, overwriting image result with fixed colour. And then doing that again outside of branch.

    – keltar
    Nov 28 '18 at 5:02











  • Thanks! It partially worked.

    – Bruno Peres
    Nov 29 '18 at 19:27














  • 2





    In second if branch you RenderCopy and then immediately FillRect to the same rectangle, overwriting image result with fixed colour. And then doing that again outside of branch.

    – keltar
    Nov 28 '18 at 5:02











  • Thanks! It partially worked.

    – Bruno Peres
    Nov 29 '18 at 19:27








2




2





In second if branch you RenderCopy and then immediately FillRect to the same rectangle, overwriting image result with fixed colour. And then doing that again outside of branch.

– keltar
Nov 28 '18 at 5:02





In second if branch you RenderCopy and then immediately FillRect to the same rectangle, overwriting image result with fixed colour. And then doing that again outside of branch.

– keltar
Nov 28 '18 at 5:02













Thanks! It partially worked.

– Bruno Peres
Nov 29 '18 at 19:27





Thanks! It partially worked.

– Bruno Peres
Nov 29 '18 at 19:27












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