view test/testsprite2.c @ 3473:7bdc10624cba

This is terrible, but the OpenGL standard says that lines are half open, which means that one endpoint is not covered so adjoining lines don't overlap. It also doesn't define which end is open, and indeed Mac OS X and Linux differ. Mac OS X seems to leave the second endpoint open, but Linux uses the right-most endpoint for x major lines and the bottom-most endpoint for y major lines.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 21 Nov 2009 07:14:21 +0000
parents 0d7b20a4a629
children 0267b8b1595c
line wrap: on
line source

/* Simple program:  Move N sprites around on the screen as fast as possible */

#include <stdlib.h>
#include <stdio.h>
#include <time.h>

#include "common.h"

#define NUM_SPRITES	100
#define MAX_SPEED 	1

static CommonState *state;
static int num_sprites;
static SDL_TextureID *sprites;
static SDL_bool cycle_color;
static SDL_bool cycle_alpha;
static int cycle_direction = 1;
static int current_alpha = 0;
static int current_color = 0;
static SDL_Rect *positions;
static SDL_Rect *velocities;
static int sprite_w, sprite_h;
static SDL_BlendMode blendMode = SDL_BLENDMODE_MASK;
static SDL_TextureScaleMode scaleMode = SDL_TEXTURESCALEMODE_NONE;

/* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
static void
quit(int rc)
{
    if (sprites) {
        SDL_free(sprites);
    }
    if (positions) {
        SDL_free(positions);
    }
    if (velocities) {
        SDL_free(velocities);
    }
    CommonQuit(state);
    exit(rc);
}

int
LoadSprite(char *file)
{
    int i;
    SDL_Surface *temp;

    /* Load the sprite image */
    temp = SDL_LoadBMP(file);
    if (temp == NULL) {
        fprintf(stderr, "Couldn't load %s: %s", file, SDL_GetError());
        return (-1);
    }
    sprite_w = temp->w;
    sprite_h = temp->h;

    /* Set transparent pixel as the pixel at (0,0) */
    if (temp->format->palette) {
        SDL_SetColorKey(temp, SDL_SRCCOLORKEY, *(Uint8 *) temp->pixels);
    } else {
        switch (temp->format->BitsPerPixel) {
        case 15:
            SDL_SetColorKey(temp, SDL_SRCCOLORKEY,
                            (*(Uint16 *) temp->pixels) & 0x00007FFF);
            break;
        case 16:
            SDL_SetColorKey(temp, SDL_SRCCOLORKEY, *(Uint16 *) temp->pixels);
            break;
        case 24:
            SDL_SetColorKey(temp, SDL_SRCCOLORKEY,
                            (*(Uint32 *) temp->pixels) & 0x00FFFFFF);
            break;
        case 32:
            SDL_SetColorKey(temp, SDL_SRCCOLORKEY, *(Uint32 *) temp->pixels);
            break;
        }
    }

    /* Create textures from the image */
    for (i = 0; i < state->num_windows; ++i) {
        SDL_SelectRenderer(state->windows[i]);
        sprites[i] = SDL_CreateTextureFromSurface(0, temp);
        if (!sprites[i]) {
		SDL_SetColorKey(temp, 0, 0);
		sprites[i] = SDL_CreateTextureFromSurface(0, temp);
	}
        if (!sprites[i]) {
            fprintf(stderr, "Couldn't create texture: %s\n", SDL_GetError());
            SDL_FreeSurface(temp);
            return (-1);
        }
        SDL_SetTextureBlendMode(sprites[i], blendMode);
        SDL_SetTextureScaleMode(sprites[i], scaleMode);
    }
    SDL_FreeSurface(temp);

    /* We're ready to roll. :) */
    return (0);
}

void
MoveSprites(SDL_WindowID window, SDL_TextureID sprite)
{
    int i, n;
    int window_w, window_h;
    SDL_Rect temp;
    SDL_Rect *position, *velocity;

    SDL_SelectRenderer(window);

    /* Query the sizes */
    SDL_GetWindowSize(window, &window_w, &window_h);

    /* Cycle the color and alpha, if desired */
    if (cycle_color) {
        current_color += cycle_direction;
        if (current_color < 0) {
            current_color = 0;
            cycle_direction = -cycle_direction;
        }
        if (current_color > 255) {
            current_color = 255;
            cycle_direction = -cycle_direction;
        }
        SDL_SetTextureColorMod(sprite, 255, (Uint8) current_color,
                               (Uint8) current_color);
    }
    if (cycle_alpha) {
        current_alpha += cycle_direction;
        if (current_alpha < 0) {
            current_alpha = 0;
            cycle_direction = -cycle_direction;
        }
        if (current_alpha > 255) {
            current_alpha = 255;
            cycle_direction = -cycle_direction;
        }
        SDL_SetTextureAlphaMod(sprite, (Uint8) current_alpha);
    }

    /* Draw a gray background */
    SDL_SetRenderDrawColor(0xA0, 0xA0, 0xA0, 0xFF);
    SDL_RenderFill(NULL);

    /* Test points */
    SDL_SetRenderDrawColor(0xFF, 0x00, 0x00, 0xFF);
    SDL_RenderPoint(0, 0);
    SDL_RenderPoint(window_w-1, 0);
    SDL_RenderPoint(0, window_h-1);
    SDL_RenderPoint(window_w-1, window_h-1);

    /* Test horizontal and vertical lines */
    SDL_SetRenderDrawColor(0x00, 0xFF, 0x00, 0xFF);
    SDL_RenderLine(1, 0, window_w-2, 0);
    SDL_RenderLine(1, window_h-1, window_w-2, window_h-1);
    SDL_RenderLine(0, 1, 0, window_h-2);
    SDL_RenderLine(window_w-1, 1, window_w-1, window_h-2);

    /* Test fill and copy */
    SDL_SetRenderDrawColor(0xFF, 0xFF, 0xFF, 0xFF);
    temp.x = 1;
    temp.y = 1;
    temp.w = sprite_w;
    temp.h = sprite_h;
    SDL_RenderFill(&temp);
    SDL_RenderCopy(sprite, NULL, &temp);
    temp.x = window_w-sprite_w-1;
    temp.y = 1;
    temp.w = sprite_w;
    temp.h = sprite_h;
    SDL_RenderFill(&temp);
    SDL_RenderCopy(sprite, NULL, &temp);
    temp.x = 1;
    temp.y = window_h-sprite_h-1;
    temp.w = sprite_w;
    temp.h = sprite_h;
    SDL_RenderFill(&temp);
    SDL_RenderCopy(sprite, NULL, &temp);
    temp.x = window_w-sprite_w-1;
    temp.y = window_h-sprite_h-1;
    temp.w = sprite_w;
    temp.h = sprite_h;
    SDL_RenderFill(&temp);
    SDL_RenderCopy(sprite, NULL, &temp);

    /* Test diagonal lines */
    SDL_SetRenderDrawColor(0x00, 0xFF, 0x00, 0xFF);
    SDL_RenderLine(sprite_w, sprite_h,
                   window_w-sprite_w-2, window_h-sprite_h-2);
    SDL_RenderLine(window_w-sprite_w-2, sprite_h,
                   sprite_w, window_h-sprite_h-2);

    /* Move the sprite, bounce at the wall, and draw */
    n = 0;
    for (i = 0; i < num_sprites; ++i) {
        position = &positions[i];
        velocity = &velocities[i];
        position->x += velocity->x;
        if ((position->x < 0) || (position->x >= (window_w - sprite_w))) {
            velocity->x = -velocity->x;
            position->x += velocity->x;
        }
        position->y += velocity->y;
        if ((position->y < 0) || (position->y >= (window_h - sprite_h))) {
            velocity->y = -velocity->y;
            position->y += velocity->y;
        }

        /* Blit the sprite onto the screen */
        SDL_RenderCopy(sprite, NULL, position);
    }

    /* Update the screen! */
    SDL_RenderPresent();
}

int
main(int argc, char *argv[])
{
    int i, done;
    SDL_Event event;
    Uint32 then, now, frames;

    /* Initialize parameters */
    num_sprites = NUM_SPRITES;

    /* Initialize test framework */
    state = CommonCreateState(argv, SDL_INIT_VIDEO);
    if (!state) {
        return 1;
    }
    for (i = 1; i < argc;) {
        int consumed;

        consumed = CommonArg(state, i);
        if (consumed == 0) {
            consumed = -1;
            if (SDL_strcasecmp(argv[i], "--blend") == 0) {
                if (argv[i + 1]) {
                    if (SDL_strcasecmp(argv[i + 1], "none") == 0) {
                        blendMode = SDL_BLENDMODE_NONE;
                        consumed = 2;
                    } else if (SDL_strcasecmp(argv[i + 1], "mask") == 0) {
                        blendMode = SDL_BLENDMODE_MASK;
                        consumed = 2;
                    } else if (SDL_strcasecmp(argv[i + 1], "blend") == 0) {
                        blendMode = SDL_BLENDMODE_BLEND;
                        consumed = 2;
                    } else if (SDL_strcasecmp(argv[i + 1], "add") == 0) {
                        blendMode = SDL_BLENDMODE_ADD;
                        consumed = 2;
                    } else if (SDL_strcasecmp(argv[i + 1], "mod") == 0) {
                        blendMode = SDL_BLENDMODE_MOD;
                        consumed = 2;
                    }
                }
            } else if (SDL_strcasecmp(argv[i], "--scale") == 0) {
                if (argv[i + 1]) {
                    if (SDL_strcasecmp(argv[i + 1], "none") == 0) {
                        scaleMode = SDL_TEXTURESCALEMODE_NONE;
                        consumed = 2;
                    } else if (SDL_strcasecmp(argv[i + 1], "fast") == 0) {
                        scaleMode = SDL_TEXTURESCALEMODE_FAST;
                        consumed = 2;
                    } else if (SDL_strcasecmp(argv[i + 1], "slow") == 0) {
                        scaleMode = SDL_TEXTURESCALEMODE_SLOW;
                        consumed = 2;
                    } else if (SDL_strcasecmp(argv[i + 1], "best") == 0) {
                        scaleMode = SDL_TEXTURESCALEMODE_BEST;
                        consumed = 2;
                    }
                }
            } else if (SDL_strcasecmp(argv[i], "--cyclecolor") == 0) {
                cycle_color = SDL_TRUE;
                consumed = 1;
            } else if (SDL_strcasecmp(argv[i], "--cyclealpha") == 0) {
                cycle_alpha = SDL_TRUE;
                consumed = 1;
            } else if (SDL_isdigit(*argv[i])) {
                num_sprites = SDL_atoi(argv[i]);
                consumed = 1;
            }
        }
        if (consumed < 0) {
            fprintf(stderr,
                    "Usage: %s %s [--blend none|mask|blend|add|mod] [--scale none|fast|slow|best] [--cyclecolor] [--cyclealpha]\n",
                    argv[0], CommonUsage(state));
            quit(1);
        }
        i += consumed;
    }
    if (!CommonInit(state)) {
        quit(2);
    }

    /* Create the windows, initialize the renderers, and load the textures */
    sprites =
        (SDL_TextureID *) SDL_malloc(state->num_windows * sizeof(*sprites));
    if (!sprites) {
        fprintf(stderr, "Out of memory!\n");
        quit(2);
    }
    for (i = 0; i < state->num_windows; ++i) {
        SDL_SelectRenderer(state->windows[i]);
        SDL_SetRenderDrawColor(0xA0, 0xA0, 0xA0, 0xFF);
        SDL_RenderFill(NULL);
    }
    if (LoadSprite("icon.bmp") < 0) {
        quit(2);
    }

    /* Allocate memory for the sprite info */
    positions = (SDL_Rect *) SDL_malloc(num_sprites * sizeof(SDL_Rect));
    velocities = (SDL_Rect *) SDL_malloc(num_sprites * sizeof(SDL_Rect));
    if (!positions || !velocities) {
        fprintf(stderr, "Out of memory!\n");
        quit(2);
    }
    srand(time(NULL));
    if (scaleMode != SDL_TEXTURESCALEMODE_NONE) {
        sprite_w += sprite_w / 2;
        sprite_h += sprite_h / 2;
    }
    for (i = 0; i < num_sprites; ++i) {
        positions[i].x = rand() % (state->window_w - sprite_w);
        positions[i].y = rand() % (state->window_h - sprite_h);
        positions[i].w = sprite_w;
        positions[i].h = sprite_h;
        velocities[i].x = 0;
        velocities[i].y = 0;
        while (!velocities[i].x && !velocities[i].y) {
            velocities[i].x = (rand() % (MAX_SPEED * 2 + 1)) - MAX_SPEED;
            velocities[i].y = (rand() % (MAX_SPEED * 2 + 1)) - MAX_SPEED;
        }
    }

    /* Main render loop */
    frames = 0;
    then = SDL_GetTicks();
    done = 0;
    while (!done) {
        /* Check for events */
        ++frames;
        while (SDL_PollEvent(&event)) {
            CommonEvent(state, &event, &done);
            switch (event.type) {
            case SDL_WINDOWEVENT:
                switch (event.window.event) {
                case SDL_WINDOWEVENT_EXPOSED:
                    SDL_SelectRenderer(event.window.windowID);
                    SDL_SetRenderDrawColor(0xA0, 0xA0, 0xA0, 0xFF);
                    SDL_RenderFill(NULL);
                    break;
                }
                break;
            default:
                break;
            }
        }
        for (i = 0; i < state->num_windows; ++i) {
            MoveSprites(state->windows[i], sprites[i]);
        }
    }

    /* Print out some timing information */
    now = SDL_GetTicks();
    if (now > then) {
        double fps = ((double) frames * 1000) / (now - then);
        printf("%2.2f frames per second\n", fps);
    }
    quit(0);
}

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