#include "demo.h"
#include "screen.h"
+/* APPROX. 170 FPS Minimum */
+
#define BG_FILENAME "data/grise.png"
-#define MIN_SCROLL 32
+#define BB_SIZE 512 /* Let's use a power of 2. Maybe we'll zoom/rotate the effect */
+
+/* Every backBuffer scanline is guaranteed to have that many dummy pixels before and after */
+#define PIXEL_PADDING 32
+
+#define MIN_SCROLL PIXEL_PADDING
#define MAX_SCROLL (backgroundW - fb_width - MIN_SCROLL)
#define FAR_SCROLL_SPEED 50.0f
static short *displacementMap;
-static float scrollSpeedTable[REFLECTION_HEIGHT];
+static unsigned short *backBuffer;
+
+static float scrollScaleTable[REFLECTION_HEIGHT];
static float scrollTable[REFLECTION_HEIGHT];
static int scrollTableRounded[REFLECTION_HEIGHT];
static int scrollModTable[REFLECTION_HEIGHT];
+static float nearScrollAmount = 0.0f;
static struct screen scr = {
"mike",
static int init(void)
{
+ /* Allocate back buffer */
+ backBuffer = (unsigned short*) malloc(BB_SIZE * BB_SIZE * sizeof(unsigned short));
+
if (!(background = img_load_pixels(BG_FILENAME, &backgroundW, &backgroundH, IMG_FMT_RGBA32))) {
fprintf(stderr, "failed to load image " BG_FILENAME "\n");
return -1;
/* Convert to 16bpp */
convert32To16((unsigned int*)background, background, backgroundW * NORMALMAP_SCANLINE); /* Normalmap will keep its 32 bit color */
- processNormal();
-
initScrollTables();
+ processNormal();
+
+#ifdef MIKE_PC
+ return 0xCAFE;
+#else
return 0;
+#endif
}
static void destroy(void)
{
- //img_free_pixels(background);
+ free(backBuffer);
+ backBuffer = 0;
+
+ img_free_pixels(background);
}
static void start(long trans_time)
static void draw(void)
{
int scroll = MIN_SCROLL + (MAX_SCROLL - MIN_SCROLL) * mouse_x / fb_width;
- unsigned short *dst = fb_pixels;
+ unsigned short *dst = backBuffer + PIXEL_PADDING;
unsigned short *src = background + scroll;
int scanline = 0;
int i = 0;
- short *disp;
+ short *dispScanline;
int d;
lastFrameDuration = (time_msec - lastFrameTime) / 1000.0f;
lastFrameTime = time_msec;
- for (scanline = 0; scanline < fb_height; scanline++) {
+ /* First, render the horizon */
+ for (scanline = 0; scanline < HORIZON_HEIGHT; scanline++) {
memcpy(dst, src, fb_width * 2);
src += backgroundW;
- dst += fb_width;
+ dst += BB_SIZE;
}
+ /* Create scroll opffsets for all scanlines of the normalmap */
updateScrollTables(lastFrameDuration);
- dst = (unsigned short*) fb_pixels + HORIZON_HEIGHT * fb_width;
+ /* Then, render the reflection under the horizon */
+ /* dst is already in place */
src = background + HORIZON_HEIGHT * backgroundW;
- disp = displacementMap;
+ dispScanline = displacementMap;
for (scanline = 0; scanline < REFLECTION_HEIGHT; scanline++) {
for (i = 0; i < fb_width; i++) {
- d = disp[(i + scrollTableRounded[scanline]) % scrollModTable[scanline]];
+ d = dispScanline[(i + scrollTableRounded[scanline]) % scrollModTable[scanline]];
*dst++ = src[i + scroll + d];
}
src += backgroundW;
+ dst += BB_SIZE - fb_width;
+ dispScanline += backgroundW;
+ }
+
+ /* Blit effect to framebuffer */
+ src = backBuffer + PIXEL_PADDING;
+ dst = fb_pixels;
+ for (scanline = 0; scanline < fb_height; scanline++) {
+ memcpy(dst, src, fb_width * 2);
+ src += BB_SIZE;
+ dst += fb_width;
}
}
/* Scale normal with depth and unpack R component (horizontal component) */
static void processNormal() {
int scanline;
- float scale;
int i;
int x;
short maxDisplacement = 0;
dst2 = displacementMap;
for (scanline = 0; scanline < REFLECTION_HEIGHT; scanline++) {
- scale = 2.0f - (float)scanline / ((float)REFLECTION_HEIGHT - 1);
- scrollModTable[scanline] = (int) (backgroundW / scale + 0.5f);
+ scrollModTable[scanline] = (int) (backgroundW / scrollScaleTable[scanline] + 0.5f);
for (i = 0; i < backgroundW; i++) {
- x = (int)(i * scale + 0.5f);
+ x = (int)(i * scrollScaleTable[scanline] + 0.5f);
if (x < backgroundW) {
- *dst = (unsigned short)normalmap[x] & 0xFF;
+ *dst = (unsigned short)(normalmap[x] >> 8) & 0xFF;
if ((short)*dst > maxDisplacement) maxDisplacement = (short)(*dst);
if ((short)*dst < minDisplacement) minDisplacement = (short)(*dst);
} else {
for (i = 0; i < backgroundW; i++) {
/* Remember that MIN_SCROLL is the padding around the screen, so ti's the maximum displacement we can get (positive & negative) */
*dst2 = 2 * MIN_SCROLL * (*dst2 - minDisplacement) / (maxDisplacement - minDisplacement) - MIN_SCROLL;
+ *dst2 = (short)((float)*dst2 / scrollScaleTable[scanline] + 0.5f); /* Displacements must also scale with distance*/
dst2++;
}
}
}
+static float distanceScale(int scanline) {
+ float farScale, t;
+ farScale = (float)NEAR_SCROLL_SPEED / (float)FAR_SCROLL_SPEED;
+ t = (float)scanline / ((float)REFLECTION_HEIGHT - 1);
+ return 1.0f / (1.0f / farScale + (1.0f - 1.0f / farScale) * t);
+}
+
static void initScrollTables() {
int i = 0;
- float scrollSpeed = FAR_SCROLL_SPEED;
- float speedIncrement = (NEAR_SCROLL_SPEED - FAR_SCROLL_SPEED) / ((float) (REFLECTION_HEIGHT - 1));
for (i = 0; i < REFLECTION_HEIGHT; i++) {
- scrollSpeedTable[i] = scrollSpeed;
- scrollSpeed += speedIncrement;
+ scrollScaleTable[i] = distanceScale(i);
scrollTable[i] = 0.0f;
scrollTableRounded[i] = 0;
}
static void updateScrollTables(float dt) {
int i = 0;
+
+ nearScrollAmount += dt * NEAR_SCROLL_SPEED;
+ nearScrollAmount = (float) fmod(nearScrollAmount, 512.0f);
+
for (i = 0; i < REFLECTION_HEIGHT; i++) {
- scrollTable[i] += scrollSpeedTable[i] * dt;
+ scrollTable[i] = nearScrollAmount / scrollScaleTable[i];
scrollTableRounded[i] = (int)(scrollTable[i] + 0.5f) % scrollModTable[i];
}
}
projects / dosdemo / blobdiff