Merge branch 'master' of mutantstargoat.com:/home/nuclear/git/dosdemo

[dosdemo] / src / grise.c

diff --git a/src/grise.c b/src/grise.c
index e6cd7ea..ed15de0 100644 (file)
--- a/src/grise.c
+++ b/src/grise.c
@@ -33,7 +33,7 @@ static RLEBitmap rleEncode(unsigned char *pixels, unsigned int w, unsigned int h
 #define PIXEL_PADDING 32
 
 /* Make sure this is less than PIXEL_PADDING*/
-#define MAX_DISPLACEMENT 16 
+#define MAX_DISPLACEMENT 16
 
 #define MIN_SCROLL PIXEL_PADDING
 #define MAX_SCROLL (backgroundW - fb_width - MIN_SCROLL)
@@ -150,6 +150,73 @@ static void stop(long trans_time)
 {
 }
 
+
+struct {
+       int circleX[3];
+       int circleY[3];
+} wheelState;
+
+static void updateWheel(float t) {
+       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;
+       wheelState.circleX[0] = (int)(x + 0.5f) + 16;
+       wheelState.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;
+       wheelState.circleX[1] = (int)(x + 0.5f) + 16;
+       wheelState.circleY[1] = (int)(y + 0.5f) + 16;
+
+       /* 3rd circle */
+       nx = x * cos120 - y * sin120;
+       ny = y * cos120 + x * sin120;
+       x = nx;
+       y = ny;
+       wheelState.circleX[2] = (int)(x + 0.5f) + 16;
+       wheelState.circleY[2] = (int)(y + 0.5f) + 16;
+}
+
+#define WHEEL_CIRCLE_RADIUS 18
+#define WHEEL_CIRCLE_RADIUS_SQ (WHEEL_CIRCLE_RADIUS * WHEEL_CIRCLE_RADIUS)
+
+static unsigned short wheel(int x, int y) {
+       int cx, cy, count=0;
+
+       /* First circle */
+       cx = wheelState.circleX[0] - x;
+       cy = wheelState.circleY[0] - y;
+       if (cx*cx + cy*cy < WHEEL_CIRCLE_RADIUS_SQ) count++;
+
+       /* 2nd circle */
+       cx = wheelState.circleX[1] - x;
+       cy = wheelState.circleY[1] - y;
+       if (cx*cx + cy*cy < WHEEL_CIRCLE_RADIUS_SQ) count++;
+
+       /* 3rd circle */
+       cx = wheelState.circleX[2] - x;
+       cy = wheelState.circleY[2] - y;
+       if (cx*cx + cy*cy < WHEEL_CIRCLE_RADIUS_SQ) count++;
+
+       if (count >= 2) return 0xFFFF;
+
+       return 0x000F;
+}
+
 static void draw(void)
 {      
        int scroll = MIN_SCROLL + (MAX_SCROLL - MIN_SCROLL) * mouse_x / fb_width;
@@ -163,6 +230,9 @@ static void draw(void)
        lastFrameDuration = (time_msec - lastFrameTime) / 1000.0f;
        lastFrameTime = time_msec;
 
+       /* Update mini-effects here */
+       updateWheel(time_msec / 1000.0f);
+
        /* First, render the horizon */
        for (scanline = 0; scanline < HORIZON_HEIGHT; scanline++) {
                memcpy(dst, src, fb_width * 2);
@@ -204,6 +274,12 @@ static void draw(void)
        /* Then after displacement, blit the objects */
        for (i = 0; i < 5; i++) rleBlit(backBuffer + PIXEL_PADDING, fb_width, fb_height, BB_SIZE, grobj, 134 + (i-3) * 60, 100);
 
+       for (scanline = 0; scanline < 32; scanline++) {
+               for (i = 0; i < 32; i++) {
+                       backBuffer[PIXEL_PADDING + scanline * BB_SIZE + i] = wheel(i, scanline);
+               }
+       }
+
        /* Blit effect to framebuffer */
        src = backBuffer + PIXEL_PADDING;
        dst = vmem_back;
@@ -316,6 +392,8 @@ static void updateScrollTables(float dt) {
 #define RLE_FILL_COLOR 0
 #define RLE_FILL_COLOR_32 ((RLE_FILL_COLOR << 16) | RLE_FILL_COLOR)
 
+#define RLE_FIXED_BITS 16
+
 static RLEBitmap rleCreate(unsigned int w, unsigned int h) {
        RLEBitmap ret;
        ret.w = w;
@@ -433,7 +511,17 @@ static void interpolateScan(unsigned char *output, unsigned char *a, unsigned ch
        ti = (*((unsigned int*)&t)) & 0x7FFFFF;
        
        for (i = 0; i < RLE_BYTES_PER_SCANLINE; i++) {
-               *output++ = ((*b++ * ti) + (*a++ * (div - ti))) >> 23;
+               if (*a == 0) {
+                       *output++ = *b++;
+                       a++;
+               } else {
+                       if (*b == 0) {
+                               *output++ = *a++;
+                               b++;
+                       } else {
+                               *output++ = ((*b++ * ti) + (*a++ * (div - ti))) >> 23;
+                       }
+               }
        }
 }
 
@@ -452,11 +540,16 @@ static void rleBlitScale(unsigned short *dst, int dstW, int dstH, int dstStride,
 
        int blitW = (int) (bitmap.w * scaleX + 0.5f);
        int blitH = (int)(bitmap.h * scaleY + 0.5f);
+
+       /* From this point on, scaleY will be inverted */
+       scaleY = 1.0f / scaleY;
+
+       int scaleXFixed = (int)(scaleX * (float)(1 << RLE_FIXED_BITS) + 0.5f);
        
        dst += blitX + blitY * dstStride;
 
        for (scanline = blitY; scanline < blitY + blitH; scanline++) {
-               float normalScan = scanlineCounter / scaleY;
+               float normalScan = scanlineCounter * scaleY; /* ScaleY  is inverted */
                unsigned char *scan0 = bitmap.scans + RLE_BYTES_PER_SCANLINE * (int)normalScan;
                unsigned char *scan1 = scan0 + RLE_BYTES_PER_SCANLINE;
                normalScan -= (int)normalScan;
@@ -466,8 +559,8 @@ static void rleBlitScale(unsigned short *dst, int dstW, int dstH, int dstStride,
 
                if (scanline < 0 || scanline >= dstH) continue;
                for (streak = 0; streak < RLE_STREAKS_PER_SCANLINE; streak++) {
-                       streakPos = (int) ((*input++) * scaleX + 0.5f);
-                       streakLength = (int)((*input++) * scaleX + 0.5f);
+                       streakPos = (*input++ * scaleXFixed) >> RLE_FIXED_BITS;
+                       streakLength = (*input++ * scaleXFixed) >> RLE_FIXED_BITS;
 
                        if ((streakPos + blitX) <= 0) continue;
 
@@ -490,6 +583,8 @@ static void rleBlitScale(unsigned short *dst, int dstW, int dstH, int dstStride,
        }
 }
 
+
+
 static void rleBlitScaleInv(unsigned short *dst, int dstW, int dstH, int dstStride,
        RLEBitmap bitmap, int blitX, int blitY, float scaleX, float scaleY)
 {
@@ -506,10 +601,15 @@ static void rleBlitScaleInv(unsigned short *dst, int dstW, int dstH, int dstStri
        int blitW = (int)(bitmap.w * scaleX + 0.5f);
        int blitH = (int)(bitmap.h * scaleY + 0.5f);
 
+       /* From this point on, scaleY will be inverted */
+       scaleY = 1.0f / scaleY;
+
+       int scaleXFixed = (int)(scaleX * (float)(1 << RLE_FIXED_BITS) + 0.5f);
+
        dst += blitX + blitY * dstStride;
 
        for (scanline = blitY; scanline > blitY - blitH; scanline--) {
-               float normalScan = scanlineCounter / scaleY;
+               float normalScan = scanlineCounter * scaleY; /* ScaleY is inverted */
                unsigned char *scan0 = bitmap.scans + RLE_BYTES_PER_SCANLINE * (int)normalScan;
                unsigned char *scan1 = scan0 + RLE_BYTES_PER_SCANLINE;
                normalScan -= (int)normalScan;
@@ -519,8 +619,8 @@ static void rleBlitScaleInv(unsigned short *dst, int dstW, int dstH, int dstStri
 
                if (scanline < 0 || scanline >= dstH) continue;
                for (streak = 0; streak < RLE_STREAKS_PER_SCANLINE; streak++) {
-                       streakPos = (int)((*input++) * scaleX + 0.5f);
-                       streakLength = (int)((*input++) * scaleX + 0.5f);
+                       streakPos = (*input++ * scaleXFixed) >> RLE_FIXED_BITS;
+                       streakLength = (*input++ * scaleXFixed) >> RLE_FIXED_BITS;
 
                        if ((streakPos + blitX) <= 0) continue;