/**
* Draw each image of the texture to the framebuffer and then save the
* entire thing to a buffer with glReadPixels().
*/
static void
draw_and_read_texture(GLuint w, GLuint h, GLuint d, GLubyte *ref)
{
int i;
for (i = 0; i < d; i++) {
float tz = (i + 0.5f) / d;
piglit_draw_rect_tex3d(i / 8 * w, i % 8 * h, /* x/y */
w, h,
0.0, 0.0, /* tx/ty */
1.0, 1.0, /* tw/th */
tz, tz /* tz0/tz1 */);
}
for (i = 0; i < d; i += 8) {
glReadPixels(i / 8 * w, i % 8 * h,
w, h * MIN2(8, d - i),
GL_RGBA, GL_UNSIGNED_BYTE,
ref);
ref += 8 * w * h * 4;
}
}
/**
* Create a texture image with reference values. Draw a textured quad.
* Save reference image with glReadPixels().
* Loop:
* replace a sub-region of the texture image with same values
* draw test textured quad
* read test image with glReadPixels
* compare reference image to test image
* \param target GL_TEXTURE_1D/2D/3D
* \param intFormat the internal texture format
*/
static GLboolean
test_format(GLenum target, GLenum intFormat)
{
const GLenum srcFormat = GL_RGBA;
GLuint w = 128, h = 64, d = 8;
GLuint tex, i, j, k, n, t;
GLubyte *img, *ref, *testImg;
GLboolean pass = GL_TRUE;
GLuint bw, bh, wMask, hMask, dMask;
get_format_block_size(intFormat, &bw, &bh);
wMask = ~(bw-1);
hMask = ~(bh-1);
dMask = ~0;
if (target != GL_TEXTURE_3D)
d = 1;
if (target == GL_TEXTURE_1D)
h = 1;
img = (GLubyte *) malloc(w * h * d * 4);
ref = (GLubyte *) malloc(w * h * d * 4);
testImg = (GLubyte *) malloc(w * h * d * 4);
/* fill source tex image */
n = 0;
for (i = 0; i < d; i++) {
for (j = 0; j < h; j++) {
for (k = 0; k < w; k++) {
img[n++] = j * 4;
img[n++] = k * 2;
img[n++] = i * 16;
img[n++] = 255;
}
}
}
glPixelStorei(GL_UNPACK_ROW_LENGTH, w);
glPixelStorei(GL_UNPACK_IMAGE_HEIGHT, h);
glGenTextures(1, &tex);
glBindTexture(target, tex);
glTexParameteri(target, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(target, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glPixelStorei(GL_UNPACK_SKIP_PIXELS, 0);
glPixelStorei(GL_UNPACK_SKIP_ROWS, 0);
glPixelStorei(GL_UNPACK_SKIP_IMAGES, 0);
if (target == GL_TEXTURE_1D) {
glTexImage1D(target, 0, intFormat, w, 0,
srcFormat, GL_UNSIGNED_BYTE, img);
}
else if (target == GL_TEXTURE_2D) {
glTexImage2D(target, 0, intFormat, w, h, 0,
srcFormat, GL_UNSIGNED_BYTE, img);
}
else if (target == GL_TEXTURE_3D) {
glTexImage3D(target, 0, intFormat, w, h, d, 0,
srcFormat, GL_UNSIGNED_BYTE, img);
}
glEnable(target);
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
/* draw reference image */
glClear(GL_COLOR_BUFFER_BIT);
piglit_draw_rect_tex3d(0, 0, w, h, 0.0, 0.0, 1.0, 1.0, 0.0, 1.0);
glReadPixels(0, 0, w, h, GL_RGBA, GL_UNSIGNED_BYTE, ref);
for (t = 0; t < 10; t++) {
/* Choose random region of texture to update.
* Use sizes and positions that are multiples of
* the compressed block size.
*/
GLint tw = (rand() % w) & wMask;
GLint th = (rand() % h) & hMask;
GLint td = (rand() % d) & dMask;
GLint tx = (rand() % (w - tw)) & wMask;
GLint ty = (rand() % (h - th)) & hMask;
GLint tz = (rand() % (d - td)) & dMask;
assert(tx + tw <= w);
assert(ty + th <= h);
assert(tz + td <= d);
/* replace texture region (with same data) */
glPixelStorei(GL_UNPACK_SKIP_PIXELS, tx);
glPixelStorei(GL_UNPACK_SKIP_ROWS, ty);
glPixelStorei(GL_UNPACK_SKIP_IMAGES, tz);
if (target == GL_TEXTURE_1D) {
glTexSubImage1D(target, 0, tx, tw,
srcFormat, GL_UNSIGNED_BYTE, img);
}
else if (target == GL_TEXTURE_2D) {
glTexSubImage2D(target, 0, tx, ty, tw, th,
srcFormat, GL_UNSIGNED_BYTE, img);
}
else if (target == GL_TEXTURE_2D) {
glTexSubImage3D(target, 0, tx, ty, tz, tw, th, td,
srcFormat, GL_UNSIGNED_BYTE, img);
}
/* draw test image */
glClear(GL_COLOR_BUFFER_BIT);
piglit_draw_rect_tex3d(0, 0, w, h, 0.0, 0.0, 1.0, 1.0, 0.0, 1.0);
glReadPixels(0, 0, w, h, GL_RGBA, GL_UNSIGNED_BYTE, testImg);
glutSwapBuffers();
if (!equal_images(ref, testImg, w, h)) {
printf("texsubimage failed\n");
printf(" target: 0x%x\n", target);
printf(" internal format: 0x%x\n", intFormat);
printf(" region: %d, %d %d x %d\n", tx, ty, tw, th);
pass = GL_FALSE;
break;
}
}
glDisable(target);
free(img);
free(ref);
free(testImg);
glDeleteTextures(1, &tex);
return pass;
}
