X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?p=dosdemo;a=blobdiff_plain;f=src%2Fminifx.c;fp=src%2Fminifx.c;h=59a32690addc2634d9e595af9ff03043818812da;hp=0000000000000000000000000000000000000000;hb=0d60e0e144c0faf5efb9551d1d23b7463ce8a4c0;hpb=f06babe97875e6023dad1843c1f0c56639967656

diff --git a/src/minifx.c b/src/minifx.c
new file mode 100644
index 0000000..59a3269
--- /dev/null
+++ b/src/minifx.c
@@ -0,0 +1,161 @@
+#include "demo.h"
+#include "imago2.h"
+#include "screen.h"
+#include <assert.h>
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <RleBitmap.h>
+
+/* APPROX. 170 FPS Minimum */
+
+static int init(void);
+static void destroy(void);
+static void start(long trans_time);
+static void stop(long trans_time);
+static void draw(void);
+
+static void updatePropeller(float t, RleBitmap *rle);
+
+static unsigned short *backBuffer;
+
+static unsigned char miniFXBuffer[1024];
+
+static long lastFrameTime = 0;
+
+static struct screen scr = {"minifx", init, destroy, start, 0, draw};
+
+struct screen *minifx_screen(void) {
+	return &scr;
+}
+
+static int init(void) {
+	/* Allocate back buffer */
+	backBuffer = (unsigned short *)calloc(FB_WIDTH * FB_HEIGHT, sizeof(unsigned short));
+
+	return 0;
+}
+
+static void destroy(void) {
+	free(backBuffer);
+	backBuffer = 0;
+}
+
+static void start(long trans_time) { lastFrameTime = time_msec; }
+
+static void draw(void) {
+	long lastFrameDuration = (time_msec - lastFrameTime) / 1000.0f;
+	lastFrameTime = time_msec;
+    
+    int clearColor = 0x888888;
+    unsigned short clearColor16 = ((clearColor << 8) & 0xF800)	   /* R */
+			   | ((clearColor >> 5) & 0x07E0)   /* G */
+			   | ((clearColor >> 19) & 0x001F); /* B */
+    for (int i=0; i<FB_WIDTH * FB_HEIGHT; i++) {
+        backBuffer[i] = clearColor16;
+    }
+
+    /* For now create / destroy in each frame. We will manage these later */
+    RleBitmap *rle = rleCreate(32, 32);
+    
+    updatePropeller(time_msec / 1000.0f, rle);
+    int stride = FB_WIDTH;
+    /*
+    rleBlit(rle, backBuffer, FB_WIDTH, FB_HEIGHT, stride,
+			100, 100);
+    */
+    
+    rleBlitScale(rle, backBuffer, FB_WIDTH, FB_HEIGHT, stride, 50,
+		  50, 3.0, 3.0);
+    
+    rleDestroy(rle);
+
+	/* Blit effect to framebuffer */
+    memcpy(fb_pixels, backBuffer, FB_WIDTH * FB_HEIGHT * sizeof(unsigned short));
+	swap_buffers(0);
+}
+
+
+#define PROPELLER_CIRCLE_RADIUS 18
+#define PROPELLER_CIRCLE_RADIUS_SQ (PROPELLER_CIRCLE_RADIUS * PROPELLER_CIRCLE_RADIUS)
+
+static struct {
+	int circleX[3];
+	int circleY[3];
+} propellerState;
+
+static void updatePropeller(float t, RleBitmap *rle) {
+    
+    t *= 0.1; /* Slow-mo to see what happens */
+	int i, j;
+	int cx, cy, count = 0;
+	unsigned char *dst;
+	float x = 0.0f;
+	float y = 18.0f;
+	float nx, ny;
+	float cost, sint;
+	static float sin120 = 0.86602540378f;
+	static float cos120 = -0.5f;
+
+	/* Rotate */
+	sint = sin(t);
+	cost = cos(t);
+	nx = x * cost - y * sint;
+	ny = y * cost + x * sint;
+	x = nx;
+	y = ny;
+	propellerState.circleX[0] = (int)(x + 0.5f) + 16;
+	propellerState.circleY[0] = (int)(y + 0.5f) + 16;
+
+	/* Rotate by 120 degrees, for the second circle */
+	nx = x * cos120 - y * sin120;
+	ny = y * cos120 + x * sin120;
+	x = nx;
+	y = ny;
+	propellerState.circleX[1] = (int)(x + 0.5f) + 16;
+	propellerState.circleY[1] = (int)(y + 0.5f) + 16;
+
+	/* 3rd circle */
+	nx = x * cos120 - y * sin120;
+	ny = y * cos120 + x * sin120;
+	x = nx;
+	y = ny;
+	propellerState.circleX[2] = (int)(x + 0.5f) + 16;
+	propellerState.circleY[2] = (int)(y + 0.5f) + 16;
+
+	/* Write effect to the mini fx buffer*/
+	dst = miniFXBuffer;
+	for (j = 0; j < 32; j++) {
+		for (i = 0; i < 32; i++) {
+			count = 0;
+
+			/* First circle */
+			cx = propellerState.circleX[0] - i;
+			cy = propellerState.circleY[0] - j;
+			if (cx * cx + cy * cy < PROPELLER_CIRCLE_RADIUS_SQ)
+				count++;
+
+			/* 2nd circle */
+			cx = propellerState.circleX[1] - i;
+			cy = propellerState.circleY[1] - j;
+			if (cx * cx + cy * cy < PROPELLER_CIRCLE_RADIUS_SQ)
+				count++;
+
+			/* 3rd circle */
+			cx = propellerState.circleX[2] - i;
+			cy = propellerState.circleY[2] - j;
+			if (cx * cx + cy * cy < PROPELLER_CIRCLE_RADIUS_SQ)
+				count++;
+
+			*dst++ = count >= 2;
+		}
+	}
+
+	/* Then, encode to rle */
+	rleEncode(rle, miniFXBuffer, 32, 32);
+
+	/* Distribute the produced streaks so that they don't produce garbage when interpolated */
+	rleDistributeStreaks(rle);
+}