Hey, I've been gone for a long time because of school and all but I'm trying to get back to developing games. I refreshed my memory by going through the psp-programming tutorials so I'm using the graphics.c file right now and I have a problem. I need a sprite to rotate by the amount of radians I want it to because I'm making it so he will walk in the direction he is facing(assuming you're at a bird's eye view). I can get the movement fine because I know how to use cosf and sinf but I'm not sure how to get the actual sprite to rotate. I want to modify blitAlphaImageToScreen() function to apply a certain rotation in radians to the sprite so obviously I had to add an extra argument.
here is the function with a new argument for rotation in it(but I never used it):
Code:
void blitAlphaImageToScreenRot(int sx, int sy, int width, int height, Image* source, int dx, int dy,float rad)
{
if (!initialized) return;
sceKernelDcacheWritebackInvalidateAll();
guStart();
sceGuTexImage(0, source->textureWidth, source->textureHeight, source->textureWidth, (void*) source->data);
float u = 1.0f / ((float)source->textureWidth);
float v = 1.0f / ((float)source->textureHeight);
sceGuTexScale(u, v);
int j = 0;
while (j < width) {
Vertex* vertices = (Vertex*) sceGuGetMemory(2 * sizeof(Vertex));
int sliceWidth = 64;
if (j + sliceWidth > width) sliceWidth = width - j;
vertices[0].u = (sx + j);
vertices[0].v = (sy);
vertices[0].x = (dx + j);
vertices[0].y = (dy);
vertices[0].z = 0;
vertices[1].u = (sx + j + sliceWidth);
vertices[1].v = (sy + height);
vertices[1].x = (dx + j + sliceWidth);
vertices[1].y = (dy + height);
vertices[1].z = 0;
sceGuDrawArray(GU_SPRITES, GU_TEXTURE_16BIT | GU_VERTEX_16BIT | GU_TRANSFORM_2D, 2, 0, vertices);
j += sliceWidth;
}
sceGuFinish();
sceGuSync(0, 0);
}
now what should I do to make the sprite rotate from here?
need help with sprite rotation
